Meniscal Tears Research Articles

Significance of three-dimensional turbo spin-echo magnetic resonance imaging with semiquantitative assessment of knee osteoarthritis: correlation to two-dimensional routine magnetic resonance imaging

Abstract Background As one of the most prevalent chronic degenerative diseases, knee osteoarthritis (KOA) is associated with the progressive degradation of articular cartilage, meniscus, synovium, ligaments, bone, muscles, and tendons. Knee osteoarthritis affects the quality of life and can cause chronic disability worldwide. Magnetic resonance imaging (MRI) is a crucial imaging modality for the morphological assessment of cartilage and all other joint tissues involved in osteoarthritis. The objective of this study was to evaluate the effectiveness of the three-dimensional (3D) turbo spin-echo (TSE) MRI and to compare its relevance to two-dimensional (2D) routine MRI in adding additional information and in the early detection of KOA. Results Total agreement between the two techniques ranged between 82.7% (cartilage degeneration), 91.4% (osteophytes), 98.3% for bone marrow edema and periarticular cyst up to 100% of other several features regarding meniscal injury and ligamentous tear. Conclusions When compared to standard 2D TSE MRI, 3D TSE MRI demonstrates substantial to almost complete agreement and high accuracy for semiquantitative assessment of knee osteoarthritis (OA). 3D TSE MRI also takes less time, which is important for large OA studies and can be used for the detection of early knee joint changes.

Abnormal patella height may be an independent risk factor in meniscal tears: a retrospective study in paediatric patients.

The literature on factors predisposing to meniscal tears in the paediatric population focuses on concomitant injuries such as anterior cruciate ligament rupture (ACL) or abnormal meniscus morphology such as discoid menisci. Patella alta has been associated with ACL ruptures but its association with meniscal tears has not been described. The purpose of our study was to evaluate whether abnormal patella height is associated with isolated meniscus tears in skeletally immature patients METHODS: We retrospectively analysed all patients under 16 years of age who had an isolated meniscal tear diagnosis confirmed on arthroscopic surgery. We examined data on demographics, meniscal morphology and patella height using the Insall-Salvati and Caton-Dechamp ratios. We compared the incidence of meniscal tears to a literature derived sex and age matched asymptomatic control group with normal patella heights. A total of 39 patients with an isolated meniscal tear were identified (mean age 13.2years). Patella alta was present in 16 (41%). 21 had normal meniscus morphology, and 18 had a discoid meniscus. There was a significant association between patella alta and isolated meniscal tears compared to the control group (p = 0.001). Our analysis is the first to demonstrate an association between abnormal patella height and the incidence of isolated meniscal tears in skeletally immature patients. Further research of knee biomechanics is required to elicit the mechanism and quantify the risk which may be used to guide prevention strategies and management of patients who wish to participate in high-risk sporting activities.

Arthroscopic meniscal posterior root repair combined with centralization reduces medial menicus extrusion associated with posterior root tears: One-year clinical outcomes.

This study aimed to assess the short-term clinical efficacy of combining posterior meniscal root repair with meniscal centralization technology in the treatment of medial meniscus posterior root tears (MMPRTs) and notable meniscus extrusion. In this retrospective analysis, patients aged 43-76 years with only chronic posterior root tears of the medial meniscus and notable extrusion were followed up for 12-14 months. (1) persistent medial knee joint pain affecting daily life, presenting with joint space tenderness; (2) showing the ineffectiveness of conservative treatment for a minimum of 3 months; conservative treatment includes non-invasive methods such as nonsteroidal anti-inflammatory drugs, physical therapy and massage, but does not include intra-articular injections. (3) Kellgren-Lawrence Grades 0-II osteoarthritis (OA) of the knee joint; and (4) diagnosis of a posterior root tear of the medial meniscus with notable meniscus extrusion confirmed through knee-joint plain magnetic resonance imaging (MRI) scans, where coronal image revealed a meniscus body extrusion of ≥3 mm. (1) Kellgren-Lawrence Grades III-IV OA in the knee joint; (2) presence of knee joint infection or other structural damage to the knee joint; (3) history of previous knee joint surgery; (4) demonstrating joint instability or abnormal lower-limb alignment (varus deformity >5°); and (5) presence of severe mental illness, coagulation disorders, or other serious medical conditions. The Lysholms score, the Hospital for Special Surgery (HSS) knee score, the visual analogue scale (VAS) score and meniscal extrusion values were evaluated before and after surgery in 23 patients through a comparative analysis. The results of the follow-up conducted 12-14 months post-operatively indicated a significant improvement in the patients' conditions. In particular, the Lysholms scores (preoperative: 50.9 ± 10.2; 1-year post-surgery: 72.0 ± 8.4), HSS knee scores (preoperative: 45.9 ± 10.6; 1-year post-surgery: 79.1 ± 11.1) and VAS scores (preoperative: 4.0 ± 1.1; 1-year post-surgery: 0.9 ± 0.7) exhibited notable enhancements. Furthermore, compared to the preoperative values, the degree of meniscus extrusion measured by coronal MRI of the knee joint significantly improved post-operatively (preoperative: 3.7 ± 0.8 mm; 1-year post-surgery: 2.2 ± 0.6 mm). These findings all yielded a p < 0.05, signifying statistical significance. In patients with chronic MMPRTs and notable extrusion, a combination of posterior meniscal root repair and centralization technology can effectively restore meniscus function and rectify the medial meniscus displacement, resulting in favourable short-term clinical outcomes. Level IV.

Experimental Assessment between Dissimilar Techniques and Methodologies to Sports Knee Injury using Magnetic Resonance Imaging

The anterior cruciate ligaments, which are crucial for conserving the normal biomechanics of human being knees, are the majority commonly injured knee-ligaments. An anterior cruciate ligament injury is originated by a split or wrench of the anterior cruciate ligaments, which are imperative ligaments in the knee. ACL injure is mainly and frequently caused by sports like football, soccer, and the like that require quick pauses or direction changes, jumping, and landings. These days, the area of diagnostics heavily relies on magnetic resonance imaging. It is effective in determining the presence of meniscal tears and damage to the cruciate ligament. This study's primary objective is to use magnetic resonance imaging knee images to find anterior cruciate ligament tears, which can be useful in identifying issues with the knee. Inception-v3, an established deep transfer learning (DTL) model based on a DCNN was used in this study to classify anterior cruciate ligament tears in MRI scans. Classification, Preprocessing, and feature extraction are the major processes used in the current study executions. The dataset type utilized in this article of research study was built using the MRNet database. Seventy percent of the data set is used for preparation and testing, while the lingering thirty percent is utilized for performance analysis in this comparison model. The future augmented methodology can improve upon the present models' performance through the application of DL and ML techniques.

Morphometric evaluation of the proximal tibiofibular joint among patients with knee joint pain: A pilot study and literature review

Objectives: The proximal tibiofibular joint (PTFJ) serves as a crucial stabilizing component of the entire knee joint complex. Morphometric analysis of the PTFJ can lead to clinically significant conclusions for orthopedic specialists and physiotherapists. The aim of the study was to assess the values of the inclination angle of the PTFJ in the sagittal and coronal planes using magnetic resonance imaging in patients with knee pain. Material and Methods: Measurements of the inclination angle were conducted on 48 patients divided into three groups: Those with damaged medial meniscus (M), those with knee joint cartilage damage (Ca), and the control group (C), in which no deviations from normality were observed in the analyzed imaging study. Results: The mean values of the tibiofibular joint inclination angle in the frontal plane were as follows: (C) 16.927° ± 1.778; (Ca) 16.822° ± 2.537; (M) 14.958° ± 1.760. In the sagittal plane, the corresponding values were: (C) 38.155° ± 1.524; (Ca) 39.392° ± 1.927; (M) 37.471° ± 1.165. Although the mean tibiofibular joint inclination angle was lowest in the group with medial meniscus injury when compared to the control group, these differences did not reach statistical significance. Conclusion: Measuring and observing the variety of PTFJ inclination angles among patients are conducive to better understanding its influence on knee pain. The differences in the PTFJ inclination angle between groups in our pilot study were not statistically significant. Consequently, the study necessitates replication within a substantial population cohort.

THE RELATIONSHIP OF POSTERIOR TIBIAL SLOPE WITH CRUCIATE LIGAMENTS AND MENISCAL INJURIES BASED ON MRI– A PROSPECTIVE OBSERVATIONAL STUDY

Purpose: Various studies show that the disparities in the posterior tibial slope can make native cruciate ligaments and the menisci susceptible to tears. This study is to determine the relationship between posterior tibial slope with the anterior cruciate ligament, posterior cruciate ligament and meniscal injuries. Methods: A total of 72 subjects between 18 and 60 years having a history of traumatic knee pain were included in the study. All subjects were clinically examined, radiologically investigated, and the posterior tibial slope of the patients was calculated. Incidences of cruciate ligaments and menisci injury were identified. Results: In our study, the mean medial compartment posterior tibial slope and lateral compartment posterior tibial slope in all the Anterior Cruciate Ligament injured patients are 7.82 ± 2.56 and 10.53 ± 3.46. But in controls, it is 5.91 ± 4.49 and 6.24 ± 5.15, respectively. The differences are statistically significant ([Formula: see text]10). In cases with increased lateral Posterior Tibial Slope, more degeneration was seen in the lateral meniscus. Less Posterior Tibial Slope is associated with Posterior Cruciate Ligament tears. Conclusion: Anterior cruciate ligament is more prone to tears with a steeper posterior tibial slope. Lateral Meniscus tear is frequently associated with acute Anterior Cruciate Ligament injury and Medial Meniscus tear is predominantly associated with a chronic Anterior Cruciate Ligament injury. A decreased posterior tibial slope is more often associated with patients with a posterior cruciate ligament injury and is considered a risk factor for native Posterior Cruciate Ligament.

Meniscus gene expression profiling of inner and outer zone meniscus tissue compared to cartilage and passaged monolayer meniscus cells

Meniscus injuries are common and while surgical strategies have improved, there is a need for alternative therapeutics to improve long-term outcomes and prevent post-traumatic osteoarthritis. Current research efforts in regenerative therapies and tissue engineering are hindered by a lack of understanding of meniscus cell biology and a poorly defined meniscus cell phenotype. This study utilized bulk RNA-sequencing to identify unique and overlapping transcriptomic profiles in cartilage, inner and outer zone meniscus tissue, and passaged inner and outer zone meniscus cells. The greatest transcriptomic differences were identified when comparing meniscus tissue to passaged monolayer cells (> 4,600 differentially expressed genes (DEGs)) and meniscus tissue to cartilage (> 3,100 DEGs). While zonal differences exist within the meniscus tissue (205 DEGs between inner and outer zone meniscus tissue), meniscus resident cells are more similar to each other than to either cartilage or passaged monolayer meniscus cells. Additionally, we identified and validated LUM, PRRX1, and SNTB1 as potential markers for meniscus tissue and ACTA2, TAGLN, SFRP2, and FSTL1 as novel markers for meniscus cell dedifferentiation. Our data contribute significantly to the current characterization of meniscus cells and provide an important foundation for future work in meniscus cell biology, regenerative medicine, and tissue engineering.

A Comparative study of anterior cruciate ligament repair effectiveness in proximal ACL tears

Background. Anterior cruciate ligament (ACL) reconstruction is a gold standard surgical option for ACL tears. Another go-to method is primary ACL repair. The latter has its own limitations such as small range of indications – proximal tears only, which constitute a significant portion of ACL injuries. Although the primary repair has been known for a long time and is still developing, recent publications show conflicting outcomes. Aim of study was to compare functional outcomes of patients with ACL reconstruction and primary repair. Methods. During 2020-2023 we conducted randomized prospective multicenter control comparative study which included 170 patients with ACL tear types A, B, E according to Gächter classification, with injuries no older than 3 months. Patients were divided into two groups: 1st group – primary repair of ACL, 2nd group – ACL reconstruction. Knee function was assessed before surgery and 3, 6, 12, 24 months after the treatment using the IKDC 2000 and Lyshlom Knee Score. Results. Type E ACL injury prevailed in the sample. The most common associated injury in both cohorts was medial meniscus tear (39,3±0,05% and 45,3±0,05%). 15,5±0,04% patients with primary repair had chondrolabral defects, reconstruction group – 10,5±0,03%. 46,03±0,06% of 2nd and 25,35±0,05% of 1st group (p0,05) received pain relief therapy in the form of opioid analgesics. The proportion of patients requiring reoperation for ACL injury in 1st group was 3,5%, in 2nd group – 1,2%. Both groups had a statistically significant increase in functional outcomes at 3, 6, 12 months (p0,05). The difference of knee function between groups was not statistically significant (p0,05). Conclusion. Primary ACL repair still retains a large number of limitations: it cannot and should not replace ACL reconstruction, but should be used with strict adherence to the indications and surgical technique to show comparable functional outcomes.

Enhancing stability and outcomes in young Indian footballers: The synergistic effect of anterior cruciate ligament reconstruction with lateral extra-articular tenodesis – A prospective observational cohort study

Objectives: Anterior cruciate ligament (ACL) tears are frequently seen injuries in young footballers that can contribute to chronic knee instability, meniscal injuries, and increased risk of early-onset osteoarthritis if not properly treated. Materials and Methods: This study evaluated the clinical findings of combined ACL reconstruction and lateral extra-articular tenodesis (LET) in 22 male footballers aged 20–30. ACL reconstruction was carried out using hamstring autografts and LET was done utilizing a modified Lemaire procedure with iliotibial band autograft. Clinical findings were studied preoperatively and at six months and one year postoperatively utilizing the International Knee Documentation Committee (IKDC) and Tegner–Lysholm scores. Results: Mean IKDC and Tegner-Lysholm scores were similar or slightly improved at six months compared to pre-operative baselines and further increased at one year follow-up, with the improvements being statistically significant. There are no cases of graft failure occurred. Conclusion: A combination of ACL reconstruction and LET is a safe and effective treatment for ACL tears in young footballers, which can restore knee stability and allow them to go back to sports. Adding LET to ACL reconstruction may help lower the likelihood of graft failure in this high-risk population.

Self-assembling peptide hydrogel scaffold accelerates healing of patellar tendon injury: A histological and biomechanical study.

Although KI24RGDS peptide hydrogel that acts as a cell adhesion has been reported to repair tissue in meniscus injury, its effect on tendon injuries remains unknown. The purpose of this study was to clarify the effect of KI24RGDS for tendon repair based on histological and biomechanical evaluation. After introducing defects (length: 10mm; width: 3mm) at the centers of rabbits' patellar tendons, and the KI24RGDS group was implanted with KI24RGDS and observed for 8 weeks. KI24RGDS implantation resulted in limited tendon elongation and better histological scores with uniformed collagen fiber orientation and early vascularization. The failure load of the patellar tendon was higher in the KI24RGDS group than that in the defect group (p < 0.05) and no significant difference with the control group (intact patellar tendon) at 8weeks postoperatively. In conclusion, KI24RGDS administration might have therapeutic potential for tendon injuries by accelerating collagen remodeling.

Intra-Articular Injection of Human Umbilical Cord-Derived Mesenchymal Stromal Cells Reduces Radiographic Osteoarthritis in an Ovine Model.

To determine if mesenchymal stromal cells (MSCs) derived from human umbilical cords (hUC) could reduce degeneration developing when injected into the knee of a large animal model of osteoarthritis (OA). Ten million culture-expanded UC-MSCs (pooled from 3 human donors) were injected in 50 μL of tissue culture medium into the left stifle joints of 7 sheep whose medial meniscus was transected 4 weeks previously. Seven other sheep had only 50 μL of medium injected as the no treatment "control" group. After 8 weeks the sheep underwent euthanasia, the joints were excised and examined macroscopically, via x-ray and magnetic resonance imaging (MRI), both via histology for degenerative and inflammatory changes and immunohistochemically to identify any human cells within the joint tissues. Activity monitoring both before meniscus transection and euthanasia was also undertaken. There was a significant reduction in the Kellgren-Lawrence x-ray score for joints injected with hUC-MSCs compared with the control joints. Likewise, macroscopic, MRI, synovitis and OARSI histology scores were all lower (better) in the joints injected with hUC-MSCs than in the control arm, but not significantly. Activity levels and synovitis scores were similar in both groups of animals. hUC-MSCs appear to modify and reduce the development of osteoarthritic changes in the ovine stifle joint after meniscal destabilization, an injury which commonly leads to OA in humans. These results are encouraging for the potential benefit of culture expanded UC-MSCs as an allogeneic cell therapy in patients who may have early OA following a meniscal injury of the knee.

Functional outcome after arthroscopic mosaicplasty for localised osteochondral defects in the knee

Background: Knee injuries are commonly encountered in active sports persons as well as nonathletes, with approximately 60% of patients having cartilage damage with or without associated ligament and meniscal injuries. In this study, we report on the functional outcome of autologous osteochondral grafting in localised cartilage lesions of the knee. MethodsA longitudinal follow-up study was conducted on 50 patients aged between 18-55 years with symptomatic focal cartilage defect in the knee of size less than 2.0 cm2 after necessary inclusion/exclusion criteria. Management involved arthroscopic autologous osteochondral grafting. The donor cartilage was from the non–weight-bearing region of the ipsilateral knee. Other associated intra-articular injuries were addressed in the same sitting. The patients were followed up after 6 weeks, 3 months and 6 months and clinical status documented by the Lysholm Knee Function Scale (LKFS). ResultsMost patients were young active males. Clinical presentation involved pain in all participants, followed by joint line tenderness. There was at least one associated injury to other intra-articular structures in 52% of the patients. The commonest associated injury was anterior cruciate ligament (ACL) tear followed by meniscus tear. The mean size of the focal cartilage defect was 1.013 cm2, ranging from 0.8 cm2 to 1.6 cm2. The mean preoperative LKFS was 56.97 ± 1.38 (standard error). There was a statistically (p < 0.001) as well as clinically significant (clinically important difference >13.0 and patient acceptable symptomatic state >70.0) improvement in the mean Lysholm score, which was 70 ± 1.32, 81.3 ± 1.12 and 92.1 ± 1.11 at the end of 6 weeks, 3 months and 6 months respectively. Eighty-four percent of the patients showed excellent functional outcome at 6 months (LKFS >90), whereas 8% and 4% had good and fair outcomes, respectively, at 6 months (LKFS: 70–90). Two patients (4%) who had failed ACL reconstruction had poor outcome (LKFS <70)at 6 months. ConclusionMosaicplasty is an excellent procedure for managing cartilage defects of small to medium sizes, less than 2.0 cm2. The short-term results are satisfying and can accelerate rehabilitation of sports injuries. It is noteworthy that instability is a contra-indication for the procedure to succeed.

Lateral Meniscus Allograft Transplant With Capsulodesis and an Osteochondral Allograft to the Lateral Femoral Condyle

Background: Anterior cruciate ligament (ACL) injuries frequently present with lateral meniscal injuries, and when irreparable, this may lead to meniscectomy, increasing the risk for osteoarthritis. Lateral meniscal allograft transplant (LMAT) can restore knee function and proper contact pressures. When combined with osteochondral allograft (OCA) for chondral defects, results are highly positive. Indications: LMAT is indicated in relatively young patients (&lt;50 years of age) with a symptomatic, meniscus-deficient knee that has failed conservative treatment. The knee must be stable, without articular cartilage damage that cannot be repaired, and patients should be able to adhere to postoperative rehabilitation and future care. Indications for OCA include young, active patients with posttraumatic osteochondral defects, osteonecrosis, osteochondritis dissecans, large focal defects, previous cartilage repair failure, or patellofemoral joint cartilage lesions. Technique Description: After a diagnostic arthroscopy is performed and concomitant injuries are ruled out, the lateral meniscal tissue is debrided to a 1- to 2-mm rim for the recipient site preparation. Tibial sockets for root fixation are created using tibial guides and passing sutures are placed. A capsulodesis is performed to reduce meniscal extrusion by securing the lateral capsule through a transtibial tunnel to the anteromedial tibial cortex with high-strength sutures. A meniscal allograft, prepared with bone plugs, is introduced through an enlarged anterolateral portal. After it is accurately positioned, it is stabilized using Fast-Fix Flex devices and circumferential sutures. The bone plug sutures are then fixed through the tibial tunnels to the anteromedial tibial cortex with a button. The large cartilage defect is addressed with an OCA transplant, involving defect measurement, careful reaming, and press-fit insertion of a donor plug, ensuring congruent articulation. Results: Patients can expect improved clinical outcomes and high patient satisfaction with LMAT and concomitant OCA. The use of bone plugs minimizes soft tissue dissection while achieving solid osseous fixation. Discussion/Conclusions: LMAT with OCA leads to restored contact pressures to near-physiological levels, a high patient satisfaction of over 85%, and mean allograft survival of 16 years. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Lower Surgical Volume Reduces the Odds of Performing Meniscus Repair for Tears During Primary ACL Reconstruction

PurposeTo investigate the influence of surgical volume, and various patient-, injury-, and surgery-related factors, on meniscal treatment strategies in primary anterior cruciate ligament reconstruction (ACLR). MethodsThis retrospective cohort study analyzed patients with concomitant meniscal injuries undergoing primary ACLR, 2008–2022, using data from the Swedish National Knee Ligament Registry. Surgeons and clinics were stratified by total caseload (cutoff: 50 ACLRs/surgeon, 500 ACLRs/clinic) and annual volume (cutoff: 29 ACLRs/year/surgeon, 56 ACLRs/year/clinic). To assess factors influencing medial meniscus (MM) or lateral meniscus (LM) repair, adjusted multivariable logistic regression was conducted, with results presented as odds ratios (OR) and 95% confidence intervals (CI). Results20,699 patients undergoing primary ACLR with concomitant meniscal injuries were included. Lower percentages of meniscus repair were seen among surgeons with low caseload and annual volume (LCLV) (13.3-20.8%) compared to high caseload and annual volume (HCHV) surgeons (19.0-29.8%), and at LCLV clinics (11.1-18.3%) compared to HCHV clinics (21.5-33.8%), all P<0.001. Significantly decreased odds of MM repair were seen for patients operated on by LCLV surgeons (OR 0.82, 95% CI 0.70-0.96; P=0.015) or at LCLV clinics (OR 0.56, 95% CI 0.50-0.64; P<0.001. Similar results were seen for LM repair with LCLV surgeons (OR 0.83, 95% CI 0.69-1.01; P=0.067) and LCLV clinics (OR 0.62, 95% CI 0.53-0.72; P<0.001). Additionally, younger age, female sex, shorter time from injury to surgery, and ACLRs performed more recently were associated with increased odds of repair. ConclusionsLower surgical volume significantly decreased the rates and odds of performing meniscal repair during primary ACLR. In contrast, ACLRs performed during more recent years in younger age, female sex, shorter time from injury to surgery, in absence of chondral injuries, and injuries sustained during nonpivoting activities, positively influenced meniscal preservation. Level of EvidenceLevel III. Retrospective cohort study.

Ultrasound-guided injection using leucocyte-rich platelet-rich plasma for treatment of meniscal injuries in a duathlete: a case report.

There is a paucity of data regarding using platelet-rich plasma therapy for Baker's cyst-associated medial meniscal tear. To date, conservative treatments for this type of condition include aspiration of fluid effusion with steroid injection and physical therapy. When this treatment fails, arthroscopic debridement, meniscectomy, cyst decompression and open cystectomy are available surgical management options. Recurrence rates, however, are high such that even these procedures fail to provide long-term pain relief. This case study explores the benefits of leukocyte-rich platelet-rich plasma therapy in treating tears in the posterior horn of the medial meniscus with concomitant Baker's cyst. With limited studies available, this case hopes to encourage more studies to be done in the future to provide a conservative option for patients with similar cases.

Healthy but not osteoarthritic human meniscus-derived matrix scaffolds promote meniscus repair.

Meniscus tissue is commonly injured due to sports-related injuries and age-related degeneration and approximately 50% of individuals with a meniscus tear will develop post-traumatic osteoarthritis (PTOA). Given that the meniscus has limited healing potential, new therapeutic strategies are required to enhance meniscus repair. Porcine meniscus-derived matrix (MDM) scaffolds improve meniscus integrative repair, but sources of human meniscus tissue have not been investigated. Therefore, the objectives of this study were to generate healthy and osteoarthritic (OA) MDM scaffolds and to compare meniscus cellular responses and integrative repair. Meniscus cells showed high viability on both healthy and OA scaffolds. While DNA content was higher in cell-seeded OA scaffolds than cell-seeded healthy scaffolds, CCK-8, and both sGAG and collagen content were similar between scaffold types. After 28days in an ex vivo meniscus defect model, healthy and OA scaffolds had similar DNA, sGAG, and collagen content. However, the shear strength of repair was reduced in defects containing OA scaffolds compared to healthy scaffolds. In conclusion, healthy human allograft tissue is a useful source for generating MDM scaffolds that can support cellular growth, ECM production, and ex vivo integrative repair of the meniscus, highlighting the potential suitability for tissue engineering approaches to improve meniscus repair.

Letter to the Editor: Arthroscopic Partial Meniscectomy for a Degenerative Meniscus Tear Is Not Cost Effective Compared with Placebo Surgery: An Economic Evaluation Based on the FIDELITY Trial Data.

Letter to the Editor: Arthroscopic Partial Meniscectomy for a Degenerative Meniscus Tear Is Not Cost Effective Compared with Placebo Surgery: An Economic Evaluation Based on the FIDELITY Trial Data.

Correction: Artificial intelligence applied to magnetic resonance imaging reliably detects the presence, but not the location, of meniscus tears: a systematic review and meta-analysis

Correction: Artificial intelligence applied to magnetic resonance imaging reliably detects the presence, but not the location, of meniscus tears: a systematic review and meta-analysis

Assessment of meniscal extrusion with ultrasonography: a systematic review and meta-analysis

BackgroundMagnetic resonance imaging (MRI) is the imaging of choice for meniscal extrusion (ME). However, they may underappreciate the load-dependent changes of the meniscus. There is growing evidence that weight-bearing ultrasound (WB US) is more suitable, particularly in revealing occult extrusion. We therefore perform a systematic review and meta-analysis on the validity and reliability of US in diagnosing extrusion. Furthermore, we explored whether it detects differences in extrusion between loaded and unloaded positions and those with pathological (osteoarthritis and meniscal injury) and healthy knees.MethodsThe Cochrane Controlled Register of Trials, PubMed, Medline, and Embase were used to perform a systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Data pertaining to intra- and interrater reliability of US in measuring meniscal extrusion (ME), its correlation with magnetic resonance imaging (MRI), and head-to-head comparison of potential factors to influence ME were included [loading versus unloading position; osteoarthritis (OA) or pathological menisci (PM) versus healthy knees; mild versus moderate–severe knee OA]. Pooled data were analyzed by random or fixed-effects models.ResultsA total of 31 studies were included. Intraclass correlation coefficients (ICC) for intra- and interrater reliability were minimum 0.94 and 0.91, respectively. The correlation between US and MRI was (r = 0.76). US detected ME to be greater in the loaded position in all knees (healthy, p < 0.00001; OA, p < 0.00001; PM, p = 0.02). In all positions, US detected greater extrusion in OA (p < 0.0003) and PM knees (p = 0.006) compared with healthy controls. Furthermore, US revealed greater extrusion in moderate–severe OA knees (p < 0.00001).ConclusionsThis systematic review suggests ultrasonography can play an important role in the measurement of meniscal extrusion, with results comparable to that of MRI. However, to what extent it can differentiate between physiological and pathological extrusion requires further investigation, with an absolute cutoff value yet to be determined. Nevertheless, it is an appropriate investigation to track the progression of disease in those with meniscal pathologies or osteoarthritis. Furthermore, it is a feasible investigation to evaluate the meniscal function following surgery.Level of evidence: IV, Systematic review of level III–IV evidence.

Safety and efficacy of placental mesenchymal stromal cells-derived extracellular vesicles in knee osteoarthritis: a randomized, triple-blind, placebo-controlled clinical trial

BackgroundKnee osteoarthritis causes pain and disability in many people worldwide, for which no definitive treatment has yet been proposed. In this study, we investigated the safety and efficacy of placental mesenchymal stromal cells-derived extracellular vesicles in patients with knee osteoarthritis.MethodsThis triple-blind, randomized clinical trial included patients suffering from bilateral knee osteoarthritis with grade 2 or 3. The knees of each patient were randomized to intervention and control. For the intervention knee, 5 cc of placental mesenchymal stromal cells-derived extracellular vesicles were injected, and for the control knee, 5 cc of normal saline was injected. The patients’ symptoms were evaluated before the intervention and 2 and 6 months after the intervention using VAS, WOMAC questionnaire, and Lequesne index. MRI was performed before the intervention and 6 months after the intervention to evaluate retropatellar and tibiofemoral cartilage volume, medial and lateral meniscal disintegrity, ACL injury, and effusion-synovitis.Results62 knees (31 patients) were enrolled in this study. There were 31 knees as intervention and 31 knees as control. Finally, the data of 58 knees (29 patients) were analyzed, including 28 women and 1 man. The mean age of the patients was 55.38 ± 6.07 years. No statistically significant difference was detected between the two groups in clinical outcomes (including VAS, WOMAC, and Lequesne scores) before treatment and 2 and 6 months after treatment. Also, no statistically significant difference was detected between the two groups in MRI findings before treatment and 6 months after treatment. No systemic complications or severe local reactions occurred in the patients.ConclusionA single intra-articular injection of placental mesenchymal stromal cells-derived extracellular vesicles (5 cc, 7 × 109 particles/cc) is safe, but does not improve clinical symptoms or MRI findings in knee osteoarthritis beyond placebo. The protocol of this study was approved on 11 May 2022 with registration number IRCT20210423051054N1.