Search Results (202)

Focal chondral defects of the knee are a common cause of pain and functional limitation in active individuals and may predispose to early degenerative joint changes. Given the limited regenerative capacity of hyaline cartilage, biologically based surgical strategies have emerged to promote tissue repair and restore joint function. This narrative review critically examines current treatment approaches that rely on autologous cell sources and scaffold-supported regeneration. Particular emphasis is placed on techniques that stimulate endogenous repair or support chondrocyte-based tissue restoration through the use of autologous biomaterial constructs. The influence of lesion morphology, joint biomechanics, and patient-specific variables on treatment selection is discussed in detail, focusing on the differences between tibiofemoral and patellofemoral involvement. Biologically driven approaches have shown promising mid- to long-term outcomes in selected patients, and are increasingly favoured over traditional methods in specific clinical scenarios. However, the literature remains limited by heterogeneity in study design, follow-up duration, and outcome measures. This review aims to provide an evidence-based, morphology-informed framework to support the clinical decision-making process in the management of knee cartilage defects. Full article

Background/Objectives: This is the first study to examine age-related patterns of meniscal/chondral lesions in women undergoing first-time knee arthroscopy. Methods: We analyzed meniscal tear type/location and evaluated cartilage damage in femoral condyles and the tibial plateau in a medium-sized Romanian cohort (n = 241). Results: Age was associated significantly (p ≤ 0.004) with medial meniscal damage (O.R. = 1.04, 95% CI: 1.01–1.06), medial femoral condyle chondropathy (O.R. = 1.06, 95% CI: 1.03–1.10), and medial tibial plateau chondropathy (O.R. = 1.07, 95% CI: 1.02–1.12). Medial meniscus tear patterns differed significantly between age groups (p < 0.001, Cramér’s V = 0.32). Bucket-handle tears—the most common tear type—peaked in middle age (p < 0.001, Cramér’s V = 0.30). The two menisci showed different distributions of tear patterns in women aged ≥40 years (p ≤ 0.023, Cramér’s V ≤ 0.41). Meniscal tears most commonly involved the posterior third. The distribution of tear sites in menisci (medial vs. lateral) varied significantly in women aged 40–59 years (p = 0.020, Cramér’s V = 0.28). The medial femoral condyle and medial tibial plateau showed significant intergroup differences in ICRS scores (p ≤ 0.024, Cramér’s V ≤ 0.34). The frequency of ICRS grade 4 cartilage lesions increased markedly in the 40–59 age group at both sites, continuing to rise in older patients for the medial tibial plateau. Conclusions: Knee pathology in women worsens with age, especially in the medial compartment. Early screening (intervention) in middle-aged women may help prevent advanced joint damage. Full article

This study described, assessed and correlated ultrasonographic, computed tomographic, and histological findings in the sacroiliac joints of adult Warmblood horse cadavers. In total, 25 joints from 15 horses were examined post-mortem using transrectal ultrasonography and helical computed tomography. Findings on computed tomography were graded in the caudal joint third (caudally) and for the entire joint as mild, moderate, or severe. In total, 11 joints from nine horses were evaluated histologically. All joints (100%) showed abnormalities on computed tomography, and 92% (23/25) displayed abnormal ultrasonographic findings. The most common ultrasonographic findings were osteophytes (92%), joint effusion (76%), and sacral/iliac bone modeling (76%). Computed tomography revealed osteophytes (92% caudally, 100% overall), sclerosis (72% caudally, 88% overall), subchondral bone lesions (60% caudally, 88% overall), and enthesophytes (60% caudally, 68% overall). The most severe CT findings occurred caudally (44%), whereas 24% occurred cranially,16% in the mid portion of the SIJ, and 16% were multifocally present in the SIJ Histological analysis showed degenerative changes in the cartilage, subchondral bone, and the joint capsule. Horses with more pronounced imaging abnormalities also showed corresponding histological degeneration. Significant correlations were found between computed tomographic findings caudally and in the entire joint (r_s = 0.915, p < 0.001, n = 25), and between imaging and histological findings (computed tomography: r_s = 0.731, p = 0.011, n = 11; ultrasonography: r_s = 0.67, p = 0.024, n = 11). Non-significant correlations were observed between mean ultrasonographic and computed-tomographic grades (r_s = 0.35, p = 0.087, n = 25). Findings suggest these structural changes may reflect adaptation to joint loading. Transrectal ultrasonography appears suitable as a first-line diagnostic tool. However, future studies are essential to compare the diagnostic imaging findings of SIJs in asymptomatic and symptomatic horses to elucidate their clinical relevance. Full article

Osteoarthritis (OA) is the most common degenerative joint disease, characterized by articular cartilage degradation, synovial inflammation, and ligament lesions. Non-coding RNAs (ncRNAs) do not encode any protein products and play a fundamental role in regulating gene expression in several physiological processes, such as in the regulation of cartilage homeostasis. When deregulated, they affect the expression of genes involved in cartilage degradation and synovial inflammation, contributing to the onset and progression of OA. Oxidative stress is also involved in the pathogenesis of OA by contributing to the inflammatory response, degradation of the extracellular matrix, and induction of chondrocyte apoptosis. Studies in the literature show a reciprocal relationship between the altered expression of a number of ncRNAs, including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), and oxidative stress. The aim of this review is to highlight the role of oxidative stress, miRNAs, and lncRNAs and their cross-talk in OA in order to understand the main molecular mechanisms involved and to identify possible targets that may be useful for the identification and development of new diagnostic and therapeutic approaches for this disease. Full article

Degenerative joint diseases, such as osteoarthritis, are increasingly prevalent in aging populations, yet current treatments like stem cell injections face limitations in targeted delivery and efficacy. In this study, we proposed a biodegradable magnetically actuated microstructure for knee cartilage regeneration. The microstructure is composed of calcium-crosslinked alginate hydrogel embedded with magnetic nanoparticles (MNPs), allowing for precise control using an external magnetic field generated by an electromagnetic actuation (EMA) system. Fabricated via a centrifugal micro-nozzle process, the microstructures exhibited tunable sizes and uniform morphology. The proposed microstructures were characterized for their morphological, chemical, and magnetic properties, and their biodegradability and targeting ability in a phosphate-buffered saline (PBS) environment were experimentally analyzed. Experimental results demonstrated that smaller microstructures degraded more rapidly and that fewer microstructures resulted in improved targeting accuracy. In contrast, microstructures clustered at the lesion site degraded more slowly, supporting sustained therapeutic release. These results suggest that the proposed system can enhance delivery precision, minimize off-target accumulation, and reduce inflammation risks associated with residual materials. The biodegradable magnetically actuated microstructures present a promising platform for minimally invasive and site-specific cartilage therapy. Full article

Background and Objectives: Chondral and osteochondral lesions can lead to osteoarthritis if untreated, making accurate assessment of cartilage repair outcomes essential for optimizing treatment strategies. The objective of this study was to compare MOCART and MOCART 2.0 and to evaluate the clinical utility of both across different surgical cartilage repair techniques and various time points. Material and Methods: This study included 111 patients (age: 35 ± 10, 35% female) who underwent cartilage repair surgery of the knee between September 2015 and March 2022. A total of 188 postoperative magnetic resonance images were evaluated using MOCART and MOCART 2.0. The correlations between both scores, as well as to the change in Patient-Reported Outcome Measures (PROMs), were determined. Results: MOCART 2.0 scores (66 ± 13) were significantly higher than MOCART scores (58 ± 13, p < 0.001). Positive correlation was observed between scoring systems (r = 0.837, p < 0.001). There was no significant correlation between MOCART or MOCART 2.0 scores and the change in PROMs. Noticeably, there was a statistically significant correlation between both MOCART and MOCART 2.0 in the AutoCart subgroup across multiple timepoints for the change in PROMs. Conclusions: Based on radiographic–clinical outcome discordance, clinicians should not rely solely on MOCART or MOCART 2.0 scores when evaluating cartilage repair success but instead prioritize patient-reported functional improvements while using imaging as a complementary assessment tool. Full article

Small extracellular vesicles (sEVs) derived from different osteoarthritic (OA) tissues regulate OA-related biological processes through transporting their content (proteins, miRNAs, etc.) to recipient cells. This study aimed to characterize the miRNA profile of synovial fibroblasts-derived small EVs (FS_OA_sEVs) and investigate their role in inflammation in chondrocytes. Chondrocytes were isolated from macroscopically preserved and lesioned OA cartilage (C_OAmin and C_OAmax) and synovial fibroblasts from OA synovium. Synovial fibroblasts-derived small EVs (FS_OA_sEVs) were characterized according to ISEV guidelines and used for miRNA profiling and bioinformatics analysis. miR-21-5p was identified as one of the most abundant, and its target genes, such as KLF6, were enriched in OA-related processes including inflammation. Treatment of C_OAmin chondrocytes with FS_OA_sEVs resulted in decreased expression of COL2A1 and ACAN and an increase in catabolic markers MMP-3 and MMP-13. Moreover, C-OAmin receiving FS_OA_sEVs exhibited increased levels of inflammatory markers and miR-21-5p expression, resembling chondrocytes’ phenotype from lesioned OA cartilage, whereas miR-21-5p inhibition reversed their expression of inflammatory markers and miR-21-5p. Compared to C_OA min, C_OAmax chondrocytes exhibited increased miR-21-5p and inflammatory markers expression and decreased KLF6 expression. miR-21-5p inhibition in C_OAmax led to KLF6 upregulation and suppression of inflammatory mediators, whereas co-treatment with siRNA against KLF6 negated this effect, confirming a potential direct regulatory relationship between miR-21-5p and KLF6. Our results provide novel insights into the FS_OA_sEV-mediated inflammation axis, highlighting FS_OA_sEV-derived miR-21-5p as a driver of OA progression via regulating inflammation in chondrocytes. Full article

Background/Objectives: The treatment of cartilage damage is an ongoing challenge. Several techniques have been developed to address this problem. Matrix-Induced Autologous Chondrocyte Implantation (MACI) is often referred to as the “gold standard” for cartilage treatment. Numerous long-term outcome studies also have reported favorable results with Autologous Matrix-Induced Chondrogenesis (AMIC). Minced Cartilage Implantation (MCI) is a recently developed arthroscopic method. This technique has demonstrated promising outcomes, with the prospect of longer-term results still under investigation. This study aims to directly compare the patient-reported outcomes of these three techniques over a 2-year follow-up period. Methods: A total of N = 48 patients were included in the retrospective matched pair analysis (n = 16 MACI, n = 16 AMIC, n = 16 MCI). VAS, KOOS-Pain, and KOOS-Symptoms scores served as primary outcomes; the KOOS-ADL and -QOL and the Tegner Activity Scale (TAS) served as secondary outcomes. Results: All three groups did not differ from each other in the primary or secondary outcomes. Pain and function significantly improved from pre-surgery to two years after (VAS: p < 0.000; ES: η² = 0.27; KOOS-Pain: p < 0.000; ES: η² = 0.30; KOOS-Symptoms: p = 0.000; ES: η² = 0.26; KOOS-ADL: p > 0.000; ES: η² = 0.20; KOOS-QOL: p > 0.000; ES: η² = 0.30). There was no significant effect of time on the activity level. Conclusions: All three procedures show good patient-reported outcomes, low complication rates, and long graft longevity in the 2-year follow-up. Therefore, all three methods seem to be equally recommendable for the treatment of cartilage lesions. Full article

Aim: This study aims to assess the suitability of the Göttingen Mini-pig (G-MP) as a large animal model for preclinical research on articular cartilage treatment procedures. Additionally, this study compares the G-MP to the domestic pig (DP) regarding surgical anatomy, postoperative care, and the challenges associated with the follow-up period. Materials and methods: Six G-MPs and four DPs underwent a two-stage surgical procedure: first, cartilage was harvested using a superolateral approach, followed by cartilage implantation via a medial parapatellar tendon approach. Results: The superolateral approach exposed 11% (SD ± 5) of the trochlea in G-MPs and 20% in DPs. The medial parapatellar tendon approach exposed 63% (SD ± 4) of the trochlear surface and 34% (SD ± 13) of the medial femoral condyle in G-MPs, allowing for the creation of four 6 mm trochlear lesions and one medial condyle lesion in four out of six G-MPs and all DPs. Cartilage thickness was less than 1 mm in G-MPs, compared to over 2 mm in DPs. Weight gain was +4 kg/week in DPs and +0.2 kg/week in G-MPs. Conclusion: Overall, the G-MP proves to be a viable model for cartilage research, offering sufficient joint access via the dual approach, which allows for 4–5 lesions of 6 mm each. However, the thinner cartilage in G-MPs should be taken into account. Full article

The proper function and longevity of the knee joint are ensured by the knee menisci. Their susceptibility to damage and injury is one of the main risk factors for rapid cartilage loss and the development of osteoarthritis. The vascularization pattern and nutritional status of a torn meniscus determine its potential for healing and the success of meniscus surgery. Blood supply is a crucial factor in assessing healing potential. Knee cartilage volume loss and its modification often result from meniscal damage or excision, leading to osteoarthritis. Modern methods for preserving meniscal tissue are currently the treatment of choice. Magnetic resonance imaging (MRI) is the gold standard for assessing meniscus lesions. It provides a comprehensive evaluation of tear stability and progression risk. Additionally, it offers high sensitivity and specificity. Arthrography combined with computed tomography (CT) can be used for patients who are unable to undergo MRI. Other methods, such as X-ray and ultrasound, are not useful for the typical diagnosis of meniscal lesions. Minimally invasive surgery has become the gold standard for both treatment and diagnosis. Modern techniques, such as all-inside compression sutures and other suturing techniques, are also considered. In contrast, in the past, open total meniscectomy was routinely performed as the gold standard, based on the mistaken belief that the menisci were functionless. Currently, new treatment methods for meniscal lesions are being explored, including mesenchymal stem cells, synthetic implants, and platelet-rich plasma (PRP). The crucial role of the menisci in knee biomechanics drives the development of modern solutions focused on preserving meniscal tissue. Full article

(1) Background: Knee cartilage injury is at the top of the rising concerns among bone and joint disorder patients. Autologous chondrocyte implantation (ACI) is widely used to approach knee cartilage deterioration. Integrating autologous chondrocytes and periosteal patches aids in forming new cartilage-like tissue at the lesion area. This study uses a novel cell source from one-day-old porcine cartilage to fabricate a biomembrane as a substitute for periosteal membranes in cell implantation techniques for treating knee cartilage injuries. (2) Methods: Cells isolated from one-day-old porcine cartilage tissue were identified and assessed for their proliferation capability, differentiation ability, and membrane formation potential. The protein component of the biomembrane was also defined by proteomics. The cartilage repair ability was also confirmed using an in vitro transplantation model. (3) Results: Negative results for porcine infectious diseases are pivotal in selecting suitable piglets to provide cartilage tissue. The cells successfully obtained from one-day-old porcine cartilage exhibited stem-cell-like characteristics (CD34-, CD45-, CD90+, CD105+), including a high proliferation to 20 passages (doubling time: 1–2 days) and a capacity to differentiate into various cell types (osteogenesis, adipogenesis, and chondrogenesis). The stem cells were successfully applied in the fabrication of the biomembranes. The protein components of the biomembrane included an extracellular matrix and growth factors. The in vitro transplantation model showed that the biomembrane induced the repair ability of cartilage defects. (4) Conclusions: This study is the first to successfully harvest stem cells from one-day-old porcine cartilage for biomembrane fabrication for a knee cartilage injury therapeutic application. Full article

Introduction: Popliteal cysts (PCs) are occasionally accompanied by knee osteoarthritis (OA) and varus malalignment. However, whether concomitant arthroscopic excision of PCs with medial open-wedge high tibial osteotomy (MOWHTO) improves the osteoarthritic environment remains unclear. Therefore, this study assessed serial changes in C-size, medial meniscus extrusion (MME), and cartilage status for up to 2 years following an MOWHTO. Methods: This study retrospectively used serial magnetic resonance imaging (MRI) evaluations to assess 26 consecutive patients who underwent MOWHTO. Of the 26 patients, six with preoperative PCs were included. Based on the arthroscopic findings at the time of the MOWHTO, concomitant meniscal and chondral lesions, and whether or not partial meniscectomy was performed, were evaluated. All patients underwent second-look arthroscopy with plate removal 2 years postoperatively. The PC size, MME, and cartilage sub-scores in the medial compartment of the whole-organ MRI score (WORMS) were assessed by serial MRI preoperatively and at 3, 6, 18, and 24 months postoperatively. The recurrence of PCs and clinical outcomes, including the Rauschning–Lindgren grade, were also evaluated when serial MRI was performed. Moreover, changes in cartilage status were assessed using two-stage arthroscopy. Results: All patients underwent concomitant partial meniscectomy for medial meniscal tears in the posterior horn. A significant decrease in the mean size of preoperative PCs (27.4 ± 22.3 mm) was noted from 3 months postoperatively (8.7 ± 7.6 mm, p = 0.018), and thereafter. The mean size of PCs further decreased with time until 2 years (1.5 ± 4.0 mm, p = 0.018) following an MOWHTO with partial meniscectomy. Moreover, significant improvements in the MME and WORMS values were noted from 3 to 24 months postoperatively. Meanwhile, no PC recurrence occurred during the follow-up period and the preoperative Rauschning–Lindgren grade improved significantly with time after MOWHTO (p = 0.026). Furthermore, the two-stage arthroscopic assessments showed significant improvements in ICRS grade in the medial femoral condyle (p = 0.038). Conclusions: After an MOWHTO with partial meniscectomy, PCs decreased with time up to 2 years postoperatively; no recurrence occurred during the follow-up period, although cyst excision was not concomitantly performed. Furthermore, the reduction in PCs corresponded with improvements in MME and chondral lesions in the knee joint following the MOWHTO. Full article

Osteoarthritis (OA) is the most prevalent chronic joint disorder and is a major cause of disability among the elderly population. The degeneration and damage of articular cartilage associated with OA can result in a diminished range of motion in joints, subsequently impacting fundamental activities such as ambulation, standing, and grasping objects. In severe cases, it may culminate in disability. Traditional pharmacological treatments are often accompanied by various side effects, while invasive surgical procedures increase the risk of infection and thrombosis. Consequently, identifying alternative new methods for OA treatment remains a formidable challenge. With advancements in responsive hydrogel drug delivery platforms, an increasing number of strategies have emerged to enhance OA treatment protocols. Injectable response hydrogel drug delivery platforms show many advantages in treating OA, including improved biocompatibility, prolonged drug release duration, elevated drug loading capacity and enhanced sensitivity. This article reviews the recent progress of injectable responsive hydrogel drug delivery platform for OA treatment over the past few years. These innovative methodologies present new strategies and directions for future OA treatment while summarizing a series of challenges faced during the clinical transformation of injectable response hydrogel drug delivery platforms. Overall, injectable responsive hydrogel drug delivery platforms show great potential in treating OA, especially regarding improving drug retention time and stimulus-responsive release at the lesion sites. These innovative methods provide new hope for future OA treatment and point the way for clinical applications. Full article

Background: Rheumatoid arthritis (RA) tends to occur in symmetrical joints and is always accompanied by synovial hyperplasia and cartilage damage. Triptolide (TP), an extract from Tripterygium, has anti-inflammatory and immunomodulatory properties and could be used in the treatment of RA. However, its poor water solubility and the multi-system lesions caused by the use of this substance limit its clinical application. Therefore, it would be of great significance to assemble a composite nanoparticle hydrogel and apply it to a collagen-induced arthritis (CIA) mouse model to investigate the therapeutic effect and biosafety of this compound. Method: TP@HSA nanoparticles (TP@HSA NPs) were fabricated with a self-assembly method; a thermosensitive hydrogel loaded with the TP@HSA NPs (TP@HSA NP hydrogel) was prepared by using chitosan and beta- glycerophosphate (β-GP) and was then intra-articularly injected into CIA mice. The changes in joint swelling were measured with a digital caliper, and inflammation and cartilage damage were evaluated by using hematoxylin and eosin (H&E) and safranin O–fast green (SO&FG) staining, respectively. Results: TP@HSA NPs with an average diameter of 112 ± 2 nm were successfully assembled, and their encapsulation efficiency and drug loading efficiency were 47.6 ± 1.5% and 10.6 ± 3.3%, respectively. The TP@HSA NP hydrogel had a gelation temperature of 30.5 ± 0.2 °C, which allows for its injection at low temperatures and its sol–gel transformation under physiological conditions within 2 min, making it a suitable drug depot. The TP@HSA NP hydrogel was intra-articularly injected into CIA mice; it released TP locally and exerted anti-inflammatory and immunomodulatory effects, alleviating synovial inflammation and cartilage damage effectively. Conclusions: We successfully fabricated a TP@HSA NP-loaded thermosensitive hydrogel with good biosafety, which can release TP slowly for the treatment of RA. Our study provides a basis for the development of TP-based innovative preparations and has good application prospects. Full article

Treatment of articular cartilage remains a great challenge due to its limited self-repair capability. In tissue engineering, a scaffold with both mechanical strength and regenerative capacity has been highly desired. This study developed a double-network scaffold based on natural biomaterials of silk fibroin (SF) and methacrylated hyaluronic acid (MAHA) using three-dimensional (3D) printing technology. Structural and mechanical characteristics of the scaffold was first investigated. To enhance its ability of recruiting endogenous bone marrow mesenchymal stem cells (BMSCs), the scaffold was conjugated with a proven BMSC-specific-affinity peptide E7, and its biocompatibility and capacity of cell recruitment were assessed in vitro. Animal experiments were conducted to evaluate cartilage regeneration after transplantation of the described scaffolds. The SF/HA scaffolds exhibited a hierarchical macro-microporous structure with ideal mechanical properties, and offered a 3D spatial microenvironment for cell migration and proliferation. In vitro experiments demonstrated excellent biocompatibility of the scaffolds to support BMSCs proliferation, differentiation, and extracellular matrix production. In vivo, superior capacity of cartilage regeneration was displayed by the SF/MAHA + E7 scaffold as compared with microfracture and unconjugated SF/MAHA scaffold based on macroscopic, histologic and imaging evaluation. In conclusion, this structurally and functionally optimized SF/MAHA + E7 scaffold may provide a promising approach to repair articular cartilage lesions in situ. Full article