Treatment of meniscal tears: An evidence based approach

Knee Injuries in Baseball

While knee injuries account for just 7% of injuries in professional and collegiate baseball, they are the fourth most common cause of missed professional games. The 3 most common knee-related issues in baseball are patellar tendinopathy, meniscus tears, and medial collateral ligament sprains. While injuries such as anterior cruciate ligament tears and patellar dislocations are less common, they are notable due to their potentially significant effect on time missed. Treatment considerations of all these pathologies are multifactorial and should include skeletal maturity, level of play, timing of season/recruiting, and long-term goals.

The impact of smoking on meniscus surgery: a systematic review

Purpose

To provide a comprehensive, systematic review on the relationship and effects of smoking on clinical outcomes after meniscus surgery.

Methods

The following combination of keywords was entered into the electronic search engines: meniscus, meniscus repairs, meniscectomy, meniscal tear, meniscus excision AND (smoke OR smoking OR nicotine OR tobacco). The year of the study, country, type of study, number of subjects, medial/lateral/both menisci, body mass index, smoking status, mean age, gender, follow-up, type/pattern of injury, surgical implications and clinical outcomes were recorded.

Results

A total of 23 studies published in 2013-2024 were included in the analysis. In ten studies, the meniscus injury was associated with an anterior cruciate ligament (ACL) tear. In four studies, the effect of smoking on meniscal allograft transplantation (MAT) was investigated. The neutral effect of smoking on meniscus surgery was revealed in nine studies, and only one of them focused on isolated meniscus pathology and surgery. The negative effect of smoking on meniscus surgery was shown in ten papers, with four papers focused on isolated meniscus tears and six papers presenting data with concurrent ACL reconstructions.

Conclusions

This systematic review found that the results regarding the impact of smoking on meniscus repair outcomes were conflicting. Nevertheless, MAT and meniscus repair performed in the presence of concurrent ligamentous injury, both being demanding surgical procedures, require reduction of factors that may contribute to failure. Therefore, cessation of smoking in patients undergoing these procedures is highly advised.

Hybrid Hydrogels Augmented via Additive Network Integration (HANI) for Meniscal Tissue Engineering Applications

Orthopedic soft tissue injuries, such as those to the fibrocartilaginous meniscus in the knee, present a significant clinical challenge, impacting millions globally and often requiring surgical interventions that fail to fully restore mechanical function. Current bioengineered meniscal replacement options that incorporate synthetic and/or natural scaffolds have limitations in biomechanical performance and biological integration. This study introduces a novel scaffold fabrication approach, termed Hybrid Hydrogels Augmented via Additive Network Integration (HANI) with great potential for meniscal tissue engineering applications. HANI scaffolds combine cross-linked gelatin-based hydrogels with polycaprolactone (PCL) additive networks, created via Fused Deposition Modeling (FDM), to enhance mechanical strength and replicate the anisotropic properties of the meniscus. Custom Stereolithography (SLA)-printed molds ensure precise dimensional control and seamless incorporation of PCL networks within the hydrogel matrix. The mechanical evaluation of HANI scaffolds showed improvements in compressive stiffness, stress relaxation behavior, and load-bearing capacity, especially with circumferential and 3D PCL reinforcements, when compared to hydrogel scaffolds without additive networks. These findings highlight HANI's potential as a cost-effective, scalable, and tunable scaffold fabrication approach for meniscal tissue engineering applications.

Power-free knee rehabilitation robot for home-based isokinetic training

Robot-assisted isokinetic training has been widely adopted for knee rehabilitation. However, existing rehabilitation facilities are often heavy, bulky, and extremely energy-consuming, which limits the rehabilitation opportunities only at designated hospitals. In this study, we introduce a highly integrated and lightweight (52 kg) knee rehabilitation robot that can provide home-based isokinetic training without external power. By integrating a motor, torque/angle sensors, control circuit, and energy regeneration circuit into a single driver module, our robot can provide power-free isokinetic training by recycling mechanical work from the trainee. Ten postsurgical subjects were involved in an interventional randomized trial (ChiCTR2300076715, Part I) and the cross-sectional area of trained legs (experimental group) was significantly higher than that of untrained legs (control group). The primary outcomes, muscle growth (quadriceps: 5.93%, hamstrings: 10.27%) and strength improvements (quadriceps: 70%, hamstrings: 84%), achieved with our robots surpass those of existing commercial rehabilitation devices. These findings indicate that our robot presents a viable option for home-based knee rehabilitation, significantly enhancing the accessibility of effective treatment.

Epigenetic dynamics in meniscus cell migration and its zonal dependency in response to inflammatory conditions

Meniscus injuries are challenging to treat due to the tissue heterogeneity and limited treatment efficacy. Understanding meniscus cell migration, crucial for healing, remains incomplete, especially its zonal dependency. This study explores how epigenetic mechanisms affect meniscus cell migration under inflammation, focusing on healing implications. Distinct histone modifications and chromatin dynamics between inner and outer cells were observed during migration, emphasizing the need to consider these differences in repair strategies. Furthermore, tumor necrosis factor alpha (TNF-α), a proinflammatory cytokine, slows inner meniscus cell migration, while outer cells remain unaffected, indicating a zonal response. Interestingly, TNF-α differentially alters histone modifications, particularly H3K27me3, between the cell types. Transcriptome analysis showed significant gene expression changes with inner cells more affected than outer cells. Gene cluster analysis revealed different responses in chromatin remodeling, extracellular matrix assembly, and wound healing between zones. We further identified potential therapeutic targets by using epigenetic drugs, GSKJ4 (a histone demethylase inhibitor) and C646 (a histone acetyltransferase inhibitor), which restored inner meniscus cell migration under inflammatory conditions, highlighting their potential in treating meniscus tears. This highlights their potential utility in treating meniscus tear injuries. Overall, our findings elucidate the intricate interplay between epigenetic mechanisms and meniscus cell migration, along with its meniscus zonal dependency. This study provides insight into potential targets for enhancing meniscus repair and regeneration, which may lead to improved clinical outcomes for patients with meniscus injuries and osteoarthritis.

McMurray's test is influenced by perimeniscal synovitis in degenerative meniscus tears

BACKGROUND

McMurray's test is a useful physical examination in determining meniscus tears, yet its sensitivity is only 38-62%. Furthermore, the relationship between degenerative meniscus tears (DMT) and mechanical symptoms during McMurray's test is not well defined. Perimeniscal synovitis occurs in osteoarthritic (OA) knees, inducing localized symptoms such as posterior knee pain in medial meniscus posterior horn DMTs. This study aimed to determine the relationship between McMurray's test with medial meniscus DMT and perimeniscal synovitis in patients with knee OA.

METHODS

We retrospectively analyzed 60 patients who underwent medial unicompartmental knee arthroplasty (UKA) with positive (n = 20) and negative (n = 40) preoperative McMurray's tests. Preoperative magnetic resonance imaging (MRI), intraoperative gross morphology, and histological analysis of meniscus and synovium were evaluated to determine meniscal tears and perimeniscal synovitis. Univariate and multivariate regression analyses were done to determine the effects of meniscus tears and synovitis on McMurray's test results.

RESULTS

Gross morphology of the medial meniscus (MM) showed 14 out of 20 torn menisci in the McMurray's (+) group compared with 22 out of 40 in the (-) group, with no difference in meniscus tear severity among groups. The (+) group showed higher values of synovial thickness (p < 0.001) and area (p < 0.001) compared with the (-) group on magnetic resonance imaging (MRI). Histological analysis showed higher synovitis (p < 0.001) scores and expression of inflammatory markers [interleukin (IL)-1β (p < 0.001), IL-6 (p = 0.007), nerve growth factor (NGF) (p = 0.003), inducible nitric oxide synthase (iNOS) (p < 0.001)] in the perimeniscal synovium of (+) group compared with the (-) group. Multivariable logistic analysis revealed that larger synovial area [odds ratio (OR) = 1.106, p = 0.008] and a higher histologic synovitis score (OR = 2.595, p = 0.011) were independently significant predictive factors for a positive McMurray's test.

CONCLUSIONS

McMurray's test may be influenced by perimeniscal synovitis in DMT patients. The clinical implications of our results may influence not only the interpretation of McMurray's test but also the target tissue in treating mechanical symptoms related to meniscus tears.

LEVEL OF EVIDENCE

Level II.

Public perceptions of meniscus tears: Evaluating knowledge gaps and the role of education

Background

Meniscus tears are common, occurring acutely during sports or as degenerative tears with aging. Limited information exists about the public's understanding of these injuries and their management.

Hypothesis/Purpose

This study aimed to evaluate the public's baseline understanding of meniscus tear management and assess the effectiveness of an educational intervention to improve their understanding.

Study design

Level III, Cross-Sectional Study.

Methods

A 33-question survey on meniscus anatomy, injury risk, diagnosis, treatment, and surgical expectations was distributed online to adults aged 18+ over 5 months from the beginning of July. An educational video and handout were provided to improve baseline knowledge. Data analysis included descriptive statistics, ANOVA, McNemar's test, and a paired t-test to measure pre- and post-intervention changes.

Results

Baseline surveys from 245 participants showed 66.9% were women, 69.4% were aged 18-29, and 63.7% were white. 46.1% held a bachelor's degree, and 90.2% had limited knowledge of meniscus tears. 76% believed surgery was necessary, 84% thought degenerative tears were repairable, and 65% didn't understand the link to osteoarthritis. Most expected over 3 months for recovery. Higher scores were associated with male gender, healthcare experience, and prior knowledge (p < 0.05). Post-intervention, correct responses rose from 45.3% to 75% (p < 0.001) among 118 participants.

Conclusion

Significant misconceptions about meniscus tears were identified. An educational intervention notably improved knowledge of meniscus anatomy, its link to osteoarthritis, and treatment options. This underscores the importance of education in aligning patient expectations with current medical practices to enhance care quality.

Fully and Weakly Supervised Deep Learning for Meniscal Injury Classification, and Location Based on MRI

Meniscal injury is a common cause of knee joint pain and a precursor to knee osteoarthritis (KOA). The purpose of this study is to develop an automatic pipeline for meniscal injury classification and localization using fully and weakly supervised networks based on MRI images. In this retrospective study, data were from the osteoarthritis initiative (OAI). The MR images were reconstructed using a sagittal intermediate-weighted fat-suppressed turbo spin-echo sequence. (1) We used 130 knees from the OAI to develop the LGSA-UNet model which fuses the features of adjacent slices and adjusts the blocks in Siam to enable the central slice to obtain rich contextual information. (2) One thousand seven hundred and fifty-six knees from the OAI were included to establish segmentation and classification models. The segmentation model achieved a DICE coefficient ranging from 0.84 to 0.93. The AUC values ranged from 0.85 to 0.95 in the binary models. The accuracy for the three types of menisci (normal, tear, and maceration) ranged from 0.60 to 0.88. Furthermore, 206 knees from the orthopedic hospital were used as an external validation data set to evaluate the performance of the model. The segmentation and classification models still performed well on the external validation set. To compare the diagnostic performances between the deep learning (DL) models and radiologists, the external validation sets were sent to two radiologists. The binary classification model outperformed the diagnostic performance of the junior radiologist (0.82-0.87 versus 0.74-0.88). This study highlights the potential of DL in knee meniscus segmentation and injury classification which can help improve diagnostic efficiency.

Identification and culture of meniscons, meniscus cells with their pericellular matrix

BACKGROUND AIMS

Meniscus injury is highly debilitating and often results in osteoarthritis. Treatment is generally symptomatic; no regenerative treatments are available. "Chondrons," articular chondrocytes with preserved pericellular matrix, produce more hyaline cartilage extracellular matrix and improve cartilage repair. If meniscons exist in the meniscus and have similar therapeutic potential as chondrons, employing these cells has potential for meniscus cell therapy and tissue engineering. In this study, we isolated and cultured "meniscons," meniscus cells surrounded by their native pericellular matrix, and investigated cell behavior in culture compared with chondrons.

METHODS

Human meniscons were enzymatically isolated from osteoarthritic menisci and cultured up to 28 days in fibrin glue. Freshly isolated meniscons and chondrons were analyzed by histology and transmission electron microscopy. We used 5-([4,6-dichlorotriazin-2-yl]amino)fluorescein hydrochloride labeling and type VI collagen immunohistochemistry to image pericellular matrix after 0 and 28 days of culture. Gene expression was quantified using real-time polymerase chain reaction and DNA content and proteoglycan production were analyzed using biochemical assays.

RESULTS

Meniscons were successfully isolated from human meniscus tissue. The pericellular matrix of meniscons and chondrons was preserved during 28 days of culture. Meniscons and chondrons had similar cell proliferation and proteoglycan production. Meniscons and chondrons expressed similar levels of collagen type I alpha 1 chain, whereas collagen type II alpha 1 chain and aggrecan expression was lower in the meniscon population.

CONCLUSIONS

Freshly isolated meniscons and meniscons cultured for 28 days share similarities with chondrons with regard to cell proliferation, morphology and biochemical activity. Rapid isolation of meniscons (45 min) demonstrates potential for one-stage meniscus regeneration and repair, which should be confirmed in vivo.

Harnessing the potential of hyaluronic acid methacrylate (HAMA) hydrogel for clinical applications in orthopaedic diseases

The treatment of orthopaedic diseases, such as fractures and osteoarthritis, remains a significant challenge due to the complex requirements for mechanical strength and tissue repair. Hydrogels based on hyaluronic acid methacrylate (HAMA) show promise as tissue engineering materials for these conditions. Hyaluronic acid (HA) is a natural component of the extracellular matrix, known for its good compatibility. The mechanical strength of HAMA-based hydrogels can be adjusted through crosslinking and by combining them with other materials. This review provides an overview of recent research on HAMA-based hydrogels for tissue engineering applications in orthopaedic diseases. First, we summarize the techniques for the preparation and characterization of HAMA hydrogels. Next, we offer a detailed review of the use of HAMA-based hydrogels in treating conditions such as cartilage injuries, bone defects, and meniscus injuries. Additionally, we discuss the applications of HAMA-based hydrogels in other diseases related to orthopaedics. Finally, we point out the challenges and propose future directions for the clinical translation of HAMA-based hydrogels.

Translational potential statement

HAMA-based hydrogels show strong translational potential in orthopaedics due to their biocompatibility, adjustable mechanical properties, and regenerative capabilities. With ongoing research, these hydrogels are well-positioned for clinical applications, particularly in cartilage repair, meniscus injuries, and osteoarthritis treatment.

Substantial medial para-meniscal cyst with a complex meniscal tear: A case report

INTRODUCTION AND IMPORTANCE

Meniscal cysts, while infrequent with a prevalence of 1 %-8 %, may result in considerable knee discomfort and functional limitations. The cysts are categorized according to their position in relation through the meniscus, labeled as either intrameniscal or parameniscal. Although parameniscal cysts are often small and asymptomatic, they may expand and become painful with time. This case report describes an uncommon instance of a medial parameniscal cyst.

CASE PRESENTATION

A 28-year-old male presented with persistent pain and swelling in the medial aspect of his left knee, lasting for 8 months. His symptoms were exacerbated by activities such as stair climbing and general mobility. On physical examination, a firm, fluctuating mass measuring 5 × 3 cm was noted. MRI revealed a complex tear in the posterior horn of the medial meniscus, along with a cyst measuring 4.9 × 3.2 × 2.0 cm. Arthroscopy identified a degenerative medial meniscus tear, and the cyst was excised through open surgery. The patient's recovery was uneventful, with full restoration of knee function within three months.

CLINICAL DISCUSSION

Parameniscal cysts often coexist with horizontal meniscal tears, influenced by factors like knee laxity, trauma, and degeneration. MRI is the preferred diagnostic tool, but high-resolution ultrasound can be beneficial. Treatment options include conservative management and surgical interventions like partial meniscectomy, emphasizing the need for comprehensive diagnosis and appropriate management.

CONCLUSION

This unique case of a medial parameniscal cyst highlights the critical need for timely diagnosis and intervention. Surgical treatment, including meniscectomy or meniscal repair, offers significant pain relief and functional improvement, demonstrating its effectiveness in managing such cases.

Meniscectomy Reimbursement and Utilization Are Declining at Different Rates Across the United States

PURPOSE

To evaluate how arthroscopic meniscectomy utilization, reimbursement, physician billing practices, and patient populations have changed within the Medicare population from 2013 to 2021 at a national level and regional level.

METHODS

The Medicare Physician & Other Practitioners database was queried for all episodes of 2-compartment and single-compartment arthroscopic meniscectomy between 2013 and 2021. Utilization per 10,000 beneficiaries and average inflation-adjusted reimbursement were assessed. Physician practice styles, measured through changes in the services billed, and Medicare beneficiary demographic characteristics were extracted each year. The Kruskal-Wallis test was performed to compare regions.

RESULTS

Between 2013 and 2021, two-compartment meniscectomy utilization per 10,000 Medicare beneficiaries declined by 54.9% and single-compartment meniscectomy utilization declined by 54.2%. Average reimbursement declined by 9.3% and 12.5% for 2-compartment meniscectomy and single-compartment meniscectomy, respectively. In 2021, the South had the highest utilization of both 2-compartment (3.8/10,000) and single-compartment (4.7/10,000) meniscectomies while having the lowest average reimbursement for 2-compartment meniscectomy ($383.02, P < .001). Nationally, the average number of beneficiaries per surgeon performing single-compartment meniscectomy declined by 3.8% whereas the average number of billable services performed per beneficiary increased by 46.6%. The comorbidity risk score of these patients decreased by 8.7%, with the West having the healthiest patients in 2021.

CONCLUSIONS

Meniscectomy utilization and reimbursement have been declining nationally within the Medicare population. Surgeons in the South performed the most meniscectomies while having among the lowest reimbursement. The practice patterns of surgeons performing meniscectomies have been changing, with surgeons performing nearly 50% more total billable services per beneficiary while performing fewer unique billable services. Additionally, the patient population of surgeons who perform meniscectomy was healthier in 2021 than in 2013.

CLINICAL RELEVANCE

This study highlights changes in meniscectomy utilization and reimbursement over time in the face of changing evidence of meniscectomy use in elderly patients and new Medicare legislature regarding reimbursement.

Platelet-Rich Plasma Injections Do Not Improve the Recovery After Arthroscopic Partial Meniscectomy: A Double-Blind Randomized Controlled Trial

BACKGROUND

Arthroscopic meniscectomy is one of the most performed surgical procedures in orthopaedics. Different approaches have been proposed to improve patient recovery but with unsatisfactory results. Platelet-rich plasma (PRP) augmentation has been proposed as a strategy to improve the recovery after meniscectomy.

PURPOSE

To investigate the clinical benefits of an intra-articular PRP injection after meniscectomy, in terms of faster and better patient recovery.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Ninety patients were randomized into a treatment group, with arthroscopic partial meniscectomy immediately followed by a 5-mL injection of autologous conditioned plasma, and a control group with partial meniscectomy alone. Patients were evaluated at baseline and at 15, 30, 60, and 180 days of follow-up with the visual analog scale (VAS) score for pain (primary outcome), as well as with International Knee Documentation Committee subjective score, Knee injury and Osteoarthritis Outcome Score subscales, Tegner score, and EuroQol-Visual Analog Scale score. Objective evaluation was performed analyzing knee range of motion and circumference and the International Knee Documentation Committee objective score. Complications, patient judgment, and satisfaction were documented as well.

RESULTS

No major complications and an overall significant improvement in the clinical scores were observed in both groups. Overall, the comparative analysis did not demonstrate significant between-group differences in absolute values or improvements of both subjective and objective scores, as well as activity level. The improvement in terms of VAS pain score for the treatment group was significant already at 15 days (from 4.3 ± 2.5 to 2.5 ± 2.5; P = .014), while in the control group it became significant at 30 days (from 3.7 ± 2.3 to 2.0 ± 2.4; P = .004). No significant differences were observed between the 2 groups in terms of judgment of treatment results and satisfaction.

CONCLUSION

A single postoperative injection of PRP was not able to significantly improve patient recovery after arthroscopic partial meniscectomy. PRP augmentation did not provide overall benefits at a short-term follow-up (6 months) in terms of pain relief, function, objective parameters, and return-to-sport activities.

REGISTRATION

NCT02872753 (ClinicalTrials.gov identifier).

Clinical Outcomes of Exercise Rehabilitation for Degenerative Tibial Meniscal Tears: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective

This study aims to comprehensively evaluate the effectiveness of exercise rehabilitation therapy for patients with Degenerative Meniscal Lesions of the Tibia (DMLT), providing more effective and safer treatment options for DMLT patients and offering more reliable evidence-based medical recommendations.

Methods

Adhering to the PRISMA guidelines, this research conducted a literature search through databases such as PubMed, Web of Science, EMBASE, EBSCOhost, and Cochrane, with the search cut-off date being January 2024. Following the PICOS principles, a comprehensive search was conducted. Two researchers independently screened the literature and extracted data. Using R software, effect size analyses were conducted on indicators such as pain, knee joint function, lower limb muscle strength, and physical function in DMLT patients, with the significance level set at P<0.05, aiming to comprehensively assess the impact of exercise therapy on the rehabilitation outcomes for DMLT patients.

Results

The study included 12 randomized controlled trials, encompassing 1336 DMLT patients. Based on the quality assessment using the modified Jadad scale, the overall quality of the included studies was determined to be moderate.The meta-analysis showed that exercise therapy significantly reduced pain (WMD=-5.50, P<0.05), improved lower limb muscle strength (SMD=0.05, P<0.05), and enhanced physical function (SMD=0.65, P<0.05). Subgroup analyses revealed that, compared to surgery alone, exercise therapy combined with surgery had a significant effect on improving muscle strength and physical function. Functional training and home-based exercises showed more pronounced effects on specific indicators. The study results indicate that exercise therapy alone has limited effectiveness in improving knee joint function, and combining exercise with surgery does not show a significant advantage (P > 0.05). Additionally, subgroup analysis revealed no significant impact of intervention duration, exercise type, or patient age on functional improvement.

Conclusion

Exercise therapy has shown potential in alleviating pain, enhancing lower limb muscle strength, and improving mobility in patients with degenerative meniscal lesions of the tibia (DMLT). Functional training and varied rehabilitation exercises may provide effective pathways for long-term recovery in these patients.

Registration

This study has been registered in a prospective registry platform with the registration number: CRD42024518643.

Partial Meniscectomy Yields Comparable Outcomes and Failure Rates to Meniscal Repair for Horizontal Cleavage Tears, With Fewer Complication Rates but Greater Progression of Degenerative Changes

PURPOSE

To compare the clinical outcomes, failure rates, surgical complications, and postoperative radiographic changes following partial meniscectomy versus meniscal repair for horizontal cleavage tears (HCTs).

METHODS

A literature search was performed according to the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the Scopus, PubMed, and Embase computerized databases. Clinical studies evaluating partial meniscectomy or meniscal repair for HCTs were included. Demographic characteristics, surgical techniques, clinical outcomes, failure rates, complications, and radiographic assessments were recorded.

RESULTS

A total of 18 studies comprising 833 patients with HCTs were included, of which 562 patients (67.5%) were treated with partial meniscectomy and 271 (32.5%) with meniscal repair. Both types of treatments reported improved clinical outcomes, including International Knee Documentation Committee, Lysholm, Knee injury and Osteoarthritis Outcome Score, and Tegner scores. Failure rates were reported to range between 0% and 15% following partial meniscectomy and from 0% to 17.6% following repair; complications were 7.5% after partial meniscectomy and between 3.8% and 21.4% following meniscal repair. Patients undergoing meniscectomy demonstrated progression of degenerative changes on radiographic assessments.

CONCLUSIONS

Repair of HCTs in the appropriately indicated patient can result in similar patient outcomes and failure rates compared to partial meniscectomy. However, especially in patients aged 42 years and younger, a greater complication rate can be expected with repair, while a greater degree of ipsilateral compartment degeneration is seen after partial meniscectomy.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I to IV studies.

Efficacy and Long-Term Outcomes of Arthroscopic Meniscus Repair: A Systematic Review and Meta-Analysis

The objective of this systematic review and meta-analysis was to evaluate the efficacy and long-term outcomes of arthroscopic meniscus repair, focusing on success, failure, and reoperation rates. A comprehensive literature search was conducted across PubMed, EMBASE, Cochrane Library, and Scopus, including studies that involved patients undergoing arthroscopic meniscus repair with a minimum follow-up of two years. The quality of the included studies was assessed using the Cochrane Risk of Bias Tool for randomized controlled trials and the Newcastle-Ottawa Scale for observational studies. Meta-analyses were conducted using RStudio 4.3.1 software (RStudio Inc., Boston, MA), with pooled risk ratios (RR) and 95% confidence intervals (CIs) calculated for dichotomous outcomes using a random effects model. The meta-analysis included 10 studies totaling 1,004 patients. The pooled success rate for arthroscopic meniscus repair was 83% (95% CI: 77%-89%), while the pooled failure rate was 20% (95% CI: 15%-25%), and the pooled reoperation rate was 21% (95% CI: 17%-25%). Significant heterogeneity was observed across studies (I² > 50%). Subgroup analyses based on suture techniques and concurrent anterior cruciate ligament (ACL) reconstruction did not reveal significant outcome differences. Arthroscopic meniscus repair demonstrates high success rates and acceptable failure and reoperation rates, supporting its continued use in clinical practice. However, the variability in study quality and significant heterogeneity highlight the need for more rigorous, high-quality studies to refine techniques and better explore long-term outcomes.

Reoperation Rates of Meniscal Repair Are Associated With a Higher Reoperation Rate Than Meniscectomy in Patients Aged 40 and Older

PURPOSE

To compare the long-term reoperation rates of meniscectomy and meniscal repair and to determine patient and surgical factors associated with earlier reoperation among patients ≥40 years.

METHODS

A retrospective study was conducted using the IBM MarketScan Commercial Claims and Encounters Database from January 1, 2006, through December 31, 2020. Patients 40 and older who received a meniscectomy or a meniscal repair with a minimum 1-year follow-up were included. The primary outcome was ipsilateral knee reoperation during the study period. Kaplan-Meier survival curves were used to determine differences in reoperation rates for meniscal repair and meniscectomy over time. Multivariable Cox regression analysis was performed to identify factors associated with earlier time to reoperation.

RESULTS

A total of 3,026 patients (2,367 meniscectomy, 659 meniscal repair) were included. Mean follow-up was 14.5 ± 0.29 years (range, 1.0-14.91 years). There were no significant differences in baseline demographic characteristics of follow-up between the 2 groups. The survival curves of the 2 procedures significantly differed (P = .02), and the overall reoperation rate was higher after meniscal repair than meniscectomy (13.5% vs 10.1%, P = .01). However, the incidence of subsequent ipsilateral meniscectomy, meniscal repair, and knee arthroplasty procedures did not significantly differ. Multivariable Cox regression analysis identified meniscal repair, obesity, concomitant anterior cruciate ligament reconstruction, and increasing age as being significant risks for earlier reoperation, and male sex was protective.

CONCLUSIONS

In a population of patients aged ≥40 with surgically treated meniscal tears and 14.5-year average follow-up, meniscal repair was associated with higher overall reoperation with shorter survival times compared to meniscectomy. However, the indications for the 2 procedures likely differed. Additionally, obesity, older age, female sex, and concomitant anterior cruciate ligament reconstruction were risk factors for earlier reoperation.

LEVEL OF EVIDENCE

Level III, retrospective comparative case series.

All-Inside and Inside-Out Repair Techniques for Bucket-Handle Meniscus Tears Both Result in Improved Patient Outcomes and a Broad Range of Failure Rates: A Systematic Review

PURPOSE

To compare patient-reported outcomes, failure rates, risk factors for failure, and complications in patients with bucket-handle meniscus tears (BHMTs) undergoing repair with inside-out (IO) versus all-inside (AI) techniques.

METHODS

A literature search was performed using the PubMed, Embase, and Scopus databases from database inception to August 2023 according to the 2020 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. The inclusion criteria consisted of Level I to IV clinical studies published in the past 10 years with greater than 2 years of follow-up that evaluated patient-reported outcome scores and/or the incidence of failure after IO or AI repairs for BHMTs. Clinical studies not reporting outcomes or failure rates, older studies using outdated implants, animal studies, reviews, letters to the editor, case reports, cadaveric studies, and articles not written in the English language or with English-language translation were excluded. Study quality was assessed using the Methodological Index for Non-randomized Studies (MINORS) criteria. Outcomes were reported as ranges and qualitatively compared.

RESULTS

A total of 16 studies published from 2013 to 2023, consisting of 1,062 patients with BHMTs, were identified. Thirteen studies (14 cohorts, 649 patients) reported on AI repair (mean age range, 23.7-32 years) and 7 studies (7 cohorts, 413 patients) reported on IO repair (mean age range, 16.7-34.6 years). Both groups had improved postoperative Lysholm and Tegner scores. Decreased range of motion was the most commonly reported complication in the AI group (range, 2.6%-4%), whereas adhesions for arthrofibrosis were the most commonly reported complication in the IO group (n = 12; range, 6%-7.9%). The overall reported failure rate ranged from 6.9% to 20.5% within the AI group and from 0% to 20% within the IO group.

CONCLUSIONS

AI and IO repair techniques for BHMTs both result in improved Lysholm and Tegner scores. However, broad ranges of failure are reported in the literature, with overall failure rates ranging from 6.9% to 20.5% after AI repair and from 0% to 20% after IO repair. Younger age and isolated medial BHMT repair are the most frequently reported risk factors for the AI technique, whereas postoperative stiffness is the most frequently reported complication after both repair techniques.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I to IV studies.

Surgical Therapy and Tissue Engineering for Meniscal Repair

Meniscal damage is one of the prevalent causes of knee pain, swelling, instability, and functional compromise, frequently culminating in osteoarthritis (OA). Timely and appropriate interventions are crucial to relieve symptoms and prevent or delay the onset of OA. Contemporary surgical treatments include total or partial meniscectomy, meniscal repair, allograft meniscal transplantation, and synthetic meniscal implants, but each presents its specific limitations. Recently, regenerative medicine and tissue engineering have emerged as promising fields, offering innovative prospects for meniscal regeneration and repair. This review delineates current surgical methods, elucidating their specific indications, advantages, and disadvantages. Concurrently, it delves into state-of-the-art tissue engineering techniques aimed at the functional regenerative repair of meniscus. Recommendations for future research and clinical practice are also provided.

The Use of Platelet-Rich Plasma Augmentation in Meniscus Repair Results in a Lower Failure Rate than in the Control Group: A Systematic Review From Meta-analysis

Purpose

To investigate the efficacy of platelet-rich plasma (PRP) as an augmentation in meniscus repair.

Methods

A comprehensive search of PubMed, Medline (via EBSCO), ProQuest, and ScienceDirect from January to February 2023 was conducted using the terms "meniscus repair," "PRP," and "meniscus tear." Meta-analyses that investigated the rate of failure after meniscus repair were included. Studies before 2003, not in English, associated procedures during surgery, and animal studies were excluded. The included studies underwent quality appraisal and risk of bias assessment. Data were extracted from each study's text, figures, tables, and associated supplementary files and then analyzed qualitatively.

Results

The failure rate is lower in the PRP augmentation group compared with the group without augmentation, with a mean difference of 0.42, 0.50, and 0.43. Visual analog scale score was also found to be significantly lower in the treatment group, with a mean difference of 0.40, 0.76, and 6.69. However, only mean differences in Lysholm score in one of the included studies were found significant regarding functional outcomes, which can be found in the Xie et al. study with a mean difference of 3.06.

Conclusions

In this study, we found that meniscal repairs augmented with PRP have a lower failure rate.

Level of Evidence

Level IV, systematic review of Level III-IV studies.

Epigenetic Dynamics in Meniscus Cell Migration and its Zonal Dependency in Response to Inflammatory Conditions: Implications for Regeneration Strategies

Meniscus injuries pose significant challenges in clinical settings, primarily due to the intrinsic heterogeneity of the tissue and the limited efficacy of current treatments. Endogenous cell migration is crucial for the healing process, yet the regulatory mechanisms of meniscus cell migration and its zonal dependency within the meniscus are not fully understood. Thus, this study investigates the role of epigenetic mechanisms in governing meniscus cell migration under inflammatory conditions, with a focus on their implications for injury healing and regeneration. Here, we discovered that a proinflammatory cytokine, TNF-α treatment significantly impedes the migration speed of inner meniscus cells, while outer meniscus cells are unaffected, underscoring a zonal-dependent response within the meniscus. Our analysis identified distinct histone modification patterns and chromatin dynamics between inner and outer meniscus cells during migration, highlighting the necessity to consider these zonal-dependent properties in devising repair strategies. Specifically, we found that TNF-α differentially influences histone modifications, particularly H3K27me3, between the two cell types. Transcriptome analysis further revealed that TNF-α treatment induces substantial gene expression changes, with inner meniscus cells exhibiting more pronounced alterations than outer cells. Gene cluster analysis pointed to distinct responses in chromatin remodeling, extracellular matrix assembly, and wound healing processes between the zonal cell populations. Moreover, we identified potential therapeutic targets by employing existing epigenetic drugs, GSKJ4 (a histone demethylase inhibitor) and C646 (a histone acetyltransferase inhibitor), to successfully restore the migration speed of inner meniscus cells under inflammatory conditions. This highlights their potential utility in treating meniscus tear injuries. Overall, our findings elucidate the intricate interplay between epigenetic mechanisms and meniscus cell migration, along with its meniscus zonal dependency. This study provides insights into potential targets for enhancing meniscus repair and regeneration, which may lead to improved clinical outcomes for patients with meniscus injuries and osteoarthritis.

Novel Meniscus Transfer Technique: A Case Report

The meniscus is an essential component of the knee joint, acting as a shock absorber as well as assisting in the transmission of forces. Due to the meniscus importance of the knee, much of the current literature focuses on treatment techniques that can spare and repair the meniscus when it is torn. The unique vasculature of the meniscus often makes repair difficult or, in many cases, impossible. A current focus within orthopedics has been on meniscal allograft transplantation to fill this gap. The lack of a universal surgical technique for graft fixation, along with the current failure rates, demonstrates the need for further improvements. The senior author proposes a novel technique for meniscal allograft transplantation that has shown decreased blood loss and surgical time, while also reducing intra-operative trauma to the knee. This case reports a 16-year-old patient who underwent a right lateral meniscal allograft transplant following a large segmental defect tear of the lateral meniscus. The patient initially underwent arthroscopy and meniscectomy with screw fixation of the lateral femoral condyle lesion. After physical therapy, the patient experienced increased pain and swelling, with magnetic resonance imaging (MRI) demonstrating a meniscal defect unamenable to repair. The patient met indications for meniscal allograft transplantation given the failed meniscectomy, absence of cartilage loss and significant osteoarthritis, and the patient's age of less than 50 years old.

Increased Age, Operative Time, American Society of Anesthesiologists Classification, Functional Dependency, and Comorbidity Burden Are Risk Factors for Adverse Events After Meniscectomy and Meniscus Repair: 10-Year Analysis of 64,223 Patients

PURPOSE

To use the National Surgical Quality Improvement Program (NSQIP) database to identify risk factors for 30-day adverse events and hospital readmission following isolated and unilateral meniscectomy or meniscus repair.

METHODS

A retrospective review of the NSQIP database from the years 2012 to 2021 identified all patients undergoing isolated, unilateral meniscectomy or meniscus repair. Multivariable analyses were performed for each procedure to identify patient characteristics associated with any adverse event (AAE) or unplanned hospital readmission within 30 days of surgery.

RESULTS

From 2012 to 2021, 59,450 (93%) patients underwent meniscectomy, and 4,773 (7%) patients underwent meniscus repair. Overall adverse event rate was 0.95% after meniscectomy and 1.40% after repair. Risk factors for AAE after meniscectomy included increased age (odds ratio [OR] = 1.010; P = .009), increased operative time (OR = 1.003; P = 0.011), American Society of Anesthesiologists (ASA) class IV (OR = 2.048; P = .045), functional dependency (OR = 3.527; P = .001), and current smoking (OR = 1.308; P = .018). Risk factors for AAE after meniscus repair included age (OR = 1.024; P = .016), operative time (OR = 1.004; P = .038), and bleeding disorders (OR = 7.000; P = .014). ASA class III increased risk of hospital readmission after both procedures (OR = 1.906; P = .008; OR = 4.101; P = .038), and medical comorbidities of heart failure (OR = 3.924; P = .016), hypertension (OR = 1.412; P = .011), and chronic obstructive pulmonary disease (OR = 2.350; P < .001) increased readmission risk after meniscectomy only.

CONCLUSIONS

Per analysis of the American College of Surgeons (ACS)-NSQIP database, surgical treatment of meniscal tears in the knee has been performed frequently over the past 10 years, with meniscectomies comprising over 90% of cases. Increased age and operative time were associated with a modest risk of adverse events after both meniscectomy and meniscus repair. Increased comorbidity burden, evidenced by ASA class, dependent functional status, current smoking, and systemic medical conditions, such as heart failure, hypertension, chronic obstructive pulmonary disease, and bleeding disorders, greatly increased rates of unfavorable outcomes within 30 days of meniscus surgery.

LEVEL OF EVIDENCE

Level III, retrospective prognostic comparative investigation.

Horizontal Cleavage Meniscus Tear: "The Quad Tendon Augmentation Technique"

The management of medial meniscus horizontal cleavage tears can be challenging. Currently, several treatment options, including nonoperative and surgical options, have been proposed in the literature. Different repair techniques aiming to promote the healing process have been reported and have shown good outcomes. However, recurrent parameniscal cysts and decreased meniscal volume have also been reported. In this Technical Note, a novel surgical technique to repair a horizontal cleavage tear of the posterior horn of the medial meniscus is reported in young patients. The technique uses a strip of autologous quadriceps tendon to fill the void between the upper and lower meniscal leaflets followed by an all-inside compression suture. Both of these technical features aim to overcome the limitations of current repair techniques.

Is Arthroscopic Meniscectomy Associated With an Increased Risk of Total Knee Arthroplasty for Claimants in the Workers' Compensation System? A 10-Year Study of Workers' Compensation Claims From a Large Nationwide Workers' Compensation Insurance Carrier

BACKGROUND

Total knee arthroplasty (TKA) is a commonly performed knee surgery and prior arthroscopic meniscectomy (AM) has been linked to an increased risk of TKA in the general population.

OBJECTIVE

To study the relationship between AM and TKA among injured workers whose medical care is paid for under workers' compensation (WC).

METHOD

A total of 17,247 lost-time claims depicting all arthroscopic knee surgical procedures performed from 2007 to 2017 were followed to the end of 2022 and analyzed.

RESULTS

The odds ratio of undergoing a TKA for those with a preceding AM is 2.20, controlling for age, sex, and attorney involvement.

CONCLUSIONS

Undergoing an AM is associated with an increased risk of TKA in WC claimants.

Osteoarthritis Development Following Meniscectomy vs. Meniscal Repair for Posterior Medial Meniscus Injuries: A Systematic Review

This systematic review aims to evaluate critically and synthesize the existing literature on the outcomes of meniscectomy versus meniscal repair for posterior medial meniscus injuries, with a focus on osteoarthritis (OA) development. We sought to assess the incidence of OA following both treatment modalities, compare functional outcomes post-treatment, and identify factors influencing treatment choice, providing evidence-based recommendations for clinical decision-making. A comprehensive search strategy was employed across PubMed, Scopus, and Embase up until December 2023, adhering to PRISMA guidelines. The primary outcomes included OA development, functional knee outcomes, and quality of life measures. Six studies met the inclusion criteria, encompassing 298 patients. The systematic review revealed a significant association between meniscal repair and decreased progression of OA compared to meniscectomy. Meniscectomy patients demonstrated a 51.42% progression rate towards OA, significantly higher than the 21.28% observed in meniscal repair patients. Functional outcomes, as measured by the International Knee Documentation Committee (IKDC) and Lysholm scores, were notably better in the repair group, with average scores of 74.68 (IKDC) and 83.78 (Lysholm) compared to 67.55 (IKDC) and 74.56 (Lysholm) in the meniscectomy group. Furthermore, the rate of complete healing in the repair group was reported at 71.4%, as one study reported, indicating a favorable prognosis for meniscal preservation. However, these pooled data should be interpreted with consideration to the heterogeneity of the analyzed studies. Meniscal repair for posterior medial meniscus injuries is superior to meniscectomy in preventing OA development and achieving better functional outcomes and quality of life post-treatment. These findings strongly suggest the adoption of meniscal repair as the preferred treatment modality for such injuries, emphasizing the need for a paradigm shift in clinical practice towards preserving meniscal integrity to optimize patient outcomes.

All-Inside Arthroscopic Meniscus Repair for Patients Over 40 Years of Age: Is Forty the New Twenty?

INTRODUCTION

Meniscal injuries are a common challenge in orthopedic surgery. For decades, partial or total meniscectomy has been the primary surgical treatment for meniscal tears. In recent years, the increased recognition of menisci's biomechanical importance has progressively shifted the paradigm towards meniscus repair. However, meniscus-sparing surgery remains the treatment of choice for selected lesions in young and active patients, especially for young and active patients. In this study, we evaluated the effectiveness of all-inside sutures in treating meniscus tears in patients over 40.

METHODS

In our retrospective evaluation, we evaluated the clinical and functional outcomes of cases over 40 years of age with post-traumatic acute meniscus tears that received meniscus repairs using the all-inside technique. The pre-operative and post-operative functionality of treated patients were assessed using the knee injury and osteoarthritis outcome score (KOOS) score. Major complications were recorded.

RESULTS

Twenty-three cases met our inclusion criteria. Eight females and fifteen males with a mean age of 44.9 were included in our study. Their mean follow-up was 35.1 months. Before surgery, our patients' mean KOOS score was 55.4 (18-80). At the patients' latest follow-up, the value had risen to 87.4 (63-100). There was no statistical correlation between patients' age and their functional recovery. No surgical failure was recorded at the latest follow-up.

CONCLUSION

The all-inside suture technique can represent a suitable and reliable solution for suturable meniscal tears, even for patients over 40. Preserving the meniscus and restoring patients' functionality allows patients to return to their daily activities and promote their quality of life.

The Association between the Extent of the Osteoarthritic Meniscus Degeneration and Cigarette Smoking-A Pilot Study

Background and Objectives: The negative effects of smoking on the musculoskeletal system were presented by many authors, although the relationship between smoking and osteoarthritis remains unclear. The aim of this paper was to investigate the negative effects of smoking on meniscal tissue in osteoarthritic knees by microscopic examination, by adapting the Bonar scoring system and its modifications. Materials and Methods: The study involved 34 patients with varus knees, from whom 65 samples of knee menisci were obtained. The mean age in the studied group was 65.385 years. The smoking status of the patients concluded that there were 13 smokers and 21 nonsmokers. Results: Among smokers, the mean classical Bonar score was 8.42 and the mean modified Bonar score was 6.65, while nonsmokers were characterized by scores of 8.51 and 7.35, respectively. There was a statistically significant negative correlation between the number of cigarettes and the collagen in the medial meniscus (p = 0.0197). Moreover, in the medial meniscus, the modified Bonar score correlated negatively with the number of cigarettes (p = 0.0180). Similarly, such a correlation was observed between the number of cigarettes and the modified Bonar score in the lateral meniscus (p = 0.04571). Furthermore, no correlation was identified between the number of cigarettes and the classical Bonar score in the lateral meniscus. There was a statistically significant difference in the collagen variable value between the smokers and nonsmokers groups (p = 0.04525). Conclusions: The microscopic investigation showed no differences in the menisci of smokers and nonsmokers, except for the collagen, which was more organized in smokers. Moreover, the modified Bonar score was correlated negatively with the number of cigarettes, which supports the role of neovascularization in meniscus pathology under the influence of tobacco smoking.

Meniscus Tear Requiring Intraoperative Repair Does Not Influence Midterm Patient-Reported Outcomes in Operatively Treated Tibial Plateau Fractures

OBJECTIVES

Evaluate whether intraoperatively repaired lateral meniscus injuries impact midterm patient-reported outcomes in those undergoing operative fixation of tibial plateau fracture.

METHODS

DESIGN

Retrospective cohort study.

SETTING

Level I trauma center.

PATIENT SELECTION CRITERIA

All patients (n = 207) who underwent operative fixation of a tibial plateau fracture from 2016 to 2021 with a minimum of 10-month follow-up.

OUTCOME MEASURES AND COMPARISONS

The Patient-Reported Outcomes Measurement Information System Physical Function, Knee Injury and Osteoarthritis Outcome Score, and the PROMIS-Preference health utility score.

RESULTS

Overall, 207 patients were included with average follow-up of 2.9 years. Seventy-three patients (35%) underwent intraoperative lateral meniscus repair. Gender, age, body mass index, Charlson comorbidity index, days to surgery, ligamentous knee injury, open fracture, vascular injury, polytraumatic injuries, Schatzker classification, and Orthopaedic Trauma Association classification were not associated with meniscal repair ( P > 0.05). Rates of reoperation (42% vs. 31%, P = 0.11), infection (8% vs. 10%, P = 0.60), return to work (78% vs. 75%, P = 0.73), and subsequent total knee arthroplasty (8% vs. 5%, P = 0.39) were also similar between those who had a meniscal repair and those without a meniscal injury, respectively. There was no difference in Patient-Reported Outcomes Measurement Information System Physical Function (46.3 vs. 45.8, P = 0.707), PROMIS-Preference (0.51 vs. 0.50, P = 0.729), and all Knee Injury and Osteoarthritis Outcome Score domain scores at the final follow-up between those who had a meniscal repair and those without a meniscal injury, respectively.

CONCLUSIONS

In patients with an operatively treated tibial plateau fracture, the presence of a concomitant intraoperatively identified and repaired lateral meniscal tear results in similar midterm PROMs and complication rates when compared with patients without meniscal injury.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Meniscectomy is associated with a higher rate of osteoarthritis compared to meniscal repair following acute tears: a meta-analysis

PURPOSE

Meniscal tears are common and may impair knee function and biomechanics. This meta-analysis compared meniscal repair versus resection in patients with symptomatic meniscal tears in terms of patient-reported outcomes measures (PROMs), joint width, surgical failure, and rate of progression to osteoarthritis (OA) at conventional radiography.

METHODS

This study was conducted according to the 2020 PRISMA statement. In August 2023, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase. Two reviewers independently performed the analysis and a methodological quality assessment of the included studies. All the clinical investigations which compared repair versus resection of meniscal tears were accessed.

RESULTS

Data from 20 studies (31,783 patients) were collected. The mean BMI was 28.28 ± 3.2 kg/m2, and the mean age was 37.6 ± 14.0 years. The mean time elapsed from injury to surgery was 12.1 ± 10.2 months and the mean medial joint width was 4.9 ± 0.8 mm. Between studies comparability at baseline was found in age, women, BMI, time from injury to surgery and length of the follow-up, PROMs, medial joint width, and stage of OA. The resection group demonstrated a greater Lysholm score (P = 0.02). No difference was found in the International Knee Documentation Committee (P = 0.2). Nine studies reported data on the rate of failures at a mean of 63.00 ± 24.7 months. No difference was found between the two groups in terms of persistent meniscal symptoms (P = 0.8). Six studies reported data on the rate of progression to total knee arthroplasty at a mean of 48.0 ± 14.7 months follow-up. The repair group evidenced a lower rate of progression to knee arthroplasty (P = 0.0001). Six studies reported data on the rate of advanced knee OA at a mean of 48.0 ± 14.7 months of follow-up. The repair group evidenced a lower rate of advanced knee OA (P = 0.0001). No difference was found in the mean joint space width (P = 0.09).

CONCLUSION

Meniscal repair is associated with a lower progression to knee osteoarthritis at approximately six years of follow-up compared to partial meniscectomy. No difference in PROMs, medial joint width, and failures were evidenced.

LEVEL OF EVIDENCE

Level III, meta-analysis.

Outcomes of Meniscal Repair in Patients Aged 40 and Above: A Systematic Review

PURPOSE

Meniscal injuries are increasingly common in older age groups. Age is often cited as a contraindication to undergoing meniscal repair due to concerns regarding failure rates. There has recently, however, been an increasing shift towards repair in older populations. The purpose of this study was to review outcomes of meniscal repair in patients over the age of 40.

METHODS

A systematic search of the following databases was conducted of PubMed, SCOPUS, Web of Science, and Cochrane Library to identify studies reporting failure rates of patients over 40 with meniscal injuries undergoing repair. The definition of meniscus failure was noted for each study evaluated in this systematic review. Further data surrounding clinical and radiological outcomes were recorded and evaluated, when available.

RESULTS

Thirteen studies were included in this review, encompassing a total of 316 meniscal repairs in patients over the age of 40 years. The overall failure rate was found to be 15.5% (49/316) (range 0-33.3%). There was no difference in the failure rate in those over 40 vs. under 40, and the two groups had equivalent functional outcomes.

CONCLUSIONS

Age should not be considered a contra-indication for meniscal repair. Appropriately selected older patients can have acceptably low failure rates with meniscal repair and similar functional outcomes to those under the age of forty. Meniscal repairs in those over 40 achieved better functional outcomes than patients of the same age group who underwent meniscectomy.

Predictive Factors Influencing the Return to Sports Following Arthroscopic Knee Meniscectomy in Sports Persons: A Prospective Cohort Study

Meniscus tears are among the common knee injuries in sports, with arthroscopic meniscectomy being one of the most commonly performed orthopedic procedures. Return to sports of the same level following arthroscopic meniscectomy is an important aspect for athletes. Numerous factors may influence the time required for athletes to resume sports activities after meniscectomy. This prospective cohort study aimed to investigate the timeframe for returning to sports in athletes who underwent arthroscopic meniscectomy and to identify predictive factors that influence this return. Ninety sports persons who had undergone arthroscopic meniscectomy were included in this study. The patients were analyzed for their time to return to sports and nine proposed predictive factors that may influence their return to sports. Out of the 90 participants, 75 were able to return to their previous activity level, while the remaining 15 were unable to do so. Among the nine pre-defined factors studied, age older than 25 years (p < 0.0001), participation in non-contact sports (p < 0.0001), and engagement in recreational activities (p < 0.0001) were found to be statistically significant. In conclusion, this study reveals that with the increase in age, time to return to sports following arthroscopic meniscectomy increases. Additionally, athletes involved in non-contact sports and those having recreational sports activity levels experience greater delays in their return to sports as compared to athletes involved in combat and contact sports and athletes having elite and competitive sports levels, respectively.

Arthroscopic Meniscus Trephination: A Novel Technique for the Treatment of Symptomatic Meniscal Degeneration: Surgical Technique and Literature Review

Introduction

Meniscal pathology constitutes a major reason for a vast number of patients suffering from knee pain. It is, in general, attributed either to meniscal tearing or degeneration. Debridement and partial meniscectomy, or repair, when possible, is the mainstay surgical approach for refractory knee pain from meniscal degeneration or tears. Sometimes, the patient has clinical symptoms of meniscal pathology, but despite those highly suggestive clinical symptoms, the patient turns out, during knee arthroscopy, to have meniscal degeneration and hardening of the meniscus without frank tearing of the meniscus.

Surgical Technique

To initiate meniscal trephination, we first conduct a diagnostic knee arthroscopy to examine the suprapatellar space, the gutters, and the anterior knee space for any pathologies. Following this, both menisci are inspected for any signs of tearing or hardening. For the purposes of our study, the medial meniscus is considered pathological if it shows signs of degeneration or hardening, which then justifies our intervention. An 18-gauge spinal needle, manually bent for the procedure, is inserted through the portal to perform trephination on the hardened menisci. Care is taken to adequately space the needle insertion points to prevent accidental tearing. Our trephination technique aims to soften the meniscus, facilitating its ability to compact and compress when patients ambulate. Additionally, the needle insertion points help attract blood flow to the meniscus, thereby enriching it with growth factors and stem cells that may aid in improving the degenerative condition.

Conclusion

Meniscal trephination is benign and effective for meniscal degenerative pathologies. The procedure allows for a healthier meniscus, free from degeneration, that would otherwise disable patients. The intervention does not have long-term adverse effects. To this end, more comparative trials are required to confirm the effectiveness of the technique and to ensure minimal to no associated side effects.

High survival rate after the combination of intrameniscal and intraarticular infiltrations of platelet-rich plasma as conservative treatment for meniscal lesions

PURPOSE

To evaluate the efficacy of applying a combination of intrameniscal and intraarticular infiltrations of Platelet-Rich Plasma (PRP) in patients with meniscal tears, analyzing its failure rate and clinical evolution, as well as factors that may influence the positive response to this treatment.

METHODS

Three hundred and ninety-two cases out of 696 met the inclusion criteria and were included in this work. Survival and patient-reported outcome measure (PROM) were collected and analyzed. Survival rate was defined as the percentage of patients who did not undergo meniscus surgery during their follow-up time. Patients were asked to complete the Knee injury and Osteoarthritis Outcome Score (KOOS) at baseline, 6 months and 18 months. Other patient- and pathology-related variables were collected. Blood and PRP samples were randomly tested as a quality control measure. Survival and comparative statistical tests, and multivariate regression were performed for the analysis of the variables.

RESULTS

The PRP applied had a platelet concentration factor of 1.9X in respect to blood levels, with no leukocytes or erythrocytes. Thirty-eight patients required surgical intervention after treatment reaching a survival rate of 90.3% with an estimated mean survival time of 54.4 months. The type of injury (P = 0.002) and the presence of chondropathy were risk factors for surgical intervention after PRP treatment (P = 0.043). All KOOS scores showed a significant statistical increase from baseline to 6 months (N = 93) and 18 months (N = 66) (P < 0.0001). The number of cases with minimal clinically important improvement (MCII) at 6 months and 18 months post-treatment was 65 (69.9%) and 43 (65.2%), respectively.

CONCLUSION

The combination of intrameniscal and intraarticular PRP infiltrations is a valid conservative treatment for meniscal injuries avoiding the need for surgical intervention. Its efficacy is higher in horizontal tears and decreases when joint degeneration is present.

LEVEL OF EVIDENCE

Level IV.

Health-economic evaluation of meniscus tear treatments: a systematic review

PURPOSE

To evaluate the overall evidence of published health-economic evaluation studies on meniscus tear treatment.

METHODS

Our systematic review focuses on health-economic evaluation studies of meniscus tear treatment interventions found in PubMed and Embase databases. A qualitative, descriptive approach was used to analyze the studies' results and systematically report them following PRISMA guidelines. The health-economic evaluation method for each included study was categorized following one of the four approaches: partial economic evaluation (PEE), cost-effectiveness analysis (CEA), cost-benefit analysis (CBA), or cost-utility analysis (CUA). The quality of each included study was assessed using the Consensus on Health Economic Criteria (CHEC) list. Comparisons of input variables and outcomes were made, if applicable.

RESULTS

Sixteen studies were included; of these, six studies performed PEE, seven studies CUA, two studies CEA, and one study combined CBA, CUA, and CEA. The following economic comparisons were analyzed and showed the respective comparative outcomes: (1) meniscus repair was more cost-effective than arthroscopic partial meniscectomy (meniscectomy) for reparable meniscus tear; (2) non-operative treatment or physical therapy was less costly than meniscectomy for degenerative meniscus tear; (3) physical therapy with delayed meniscectomy was more cost-effective than early meniscectomy for meniscus tear with knee osteoarthritis; (4) meniscectomy without physical therapy was less costly than meniscectomy with physical therapy; (5) meniscectomy was more cost-effective than either meniscus allograft transplantation or meniscus scaffold procedure; (6) the conventional arthroscopic instrument cost was lower than laser-assisted arthroscopy in meniscectomy procedures.

CONCLUSION

Results from this review suggest that meniscus repair is the most cost-effective intervention for reparable meniscus tears. Physical therapy followed by delayed meniscectomy is the most cost-effective intervention for degenerative meniscus tears. Meniscus scaffold should be avoided, especially when implemented on a large scale.

LEVEL OF EVIDENCE

Systematic review of level IV studies.

Arthroscopic Meniscectomy vs Meniscal Repair: Comparison of Clinical Outcomes

Background Meniscal tears are the most common injury of the knee. Surgical treatment has fallen into contention recently and includes arthroscopic meniscectomy and meniscal repair. The primary aim of this study was to quantitatively evaluate patients with isolated meniscal tears and compare their outcomes with patients who have undergone arthroscopic meniscus surgery. The secondary aim of this study was to compare the clinical outcomes of patients who have undergone arthroscopic meniscectomy with patients who have undergone arthroscopic meniscal repair. Methods This comparative clinical study screened 334 patients to identify subjects who underwent arthroscopic knee surgery for isolated meniscal tears and compare them to patients with symptomatic isolated meniscal tears awaiting surgery using validated patient-reported outcome measures. These included the Knee Injury and Osteoarthritis Outcome Score, International Knee Documentation Committee Subjective Knee Form, Lysholm score, Tegner score, EuroQol-5 Dimension, and the 12-Item Short Form Health Survey. Results A total of 117 patients (Meniscal Tear group (n=36), Meniscectomy group (n=64), and Meniscal Repair group (n=17)) were included in the final data analysis. Both the Meniscectomy group and the Meniscal Repair group (mean 55-month follow-up) showed significantly better clinical outcomes than patients in the Meniscal Tear group (p<0.05). Overall, the Meniscal Repair group demonstrated superior clinical outcomes when compared to the Meniscectomy group (p<0.05). Conclusion Arthroscopic knee surgery showed significant clinical benefit at medium-term follow-up in treating patients with isolated meniscal tears. When feasible, meniscal repair should be performed preferentially over meniscectomy.

Anterolateral Radial Meniscus Tear Repair using Traction Suture and Super-Hashtag Technique

Radial meniscus tears occur commonly as traumatic tears in younger patients, as well as in association with concomitant degenerative changes. Traditional management of these tears has centered around partial meniscectomy; however, there has been a more recent trend toward preserving the meniscus and attempting repair. Because of the gapping and displacement that frequently occurs with these tears, repair is often challenging and is done under high amounts of tension. The following article describes a technique using a traction suture to aid in maintaining reduction throughout repair. This is followed by the use of a combination of techniques to form a "super-hashtag" configuration of both vertical and horizontal mattress sutures, leading to a secure repair under little tension.

Visual Cascaded-Progressive Convolutional Neural Network (C-PCNN) for Diagnosis of Meniscus Injury

OBJECTIVE

The objective of this study is to develop a novel automatic convolutional neural network (CNN) that aids in the diagnosis of meniscus injury, while enabling the visualization of lesion characteristics. This will improve the accuracy and reduce diagnosis times.

METHODS

We presented a cascaded-progressive convolutional neural network (C-PCNN) method for diagnosing meniscus injuries using magnetic resonance imaging (MRI). A total of 1396 images collected in the hospital were used for training and testing. The method used for training and testing was 5-fold cross validation. Using intraoperative arthroscopic diagnosis and MRI diagnosis as criteria, the C-PCNN was evaluated based on accuracy, sensitivity, specificity, receiver operating characteristic (ROC), and evaluation performance. At the same time, the diagnostic accuracy of doctors with the assistance of cascade- progressive convolutional neural networks was evaluated. The diagnostic accuracy of a C-PCNN assistant with an attending doctor and chief doctor was compared to evaluate the clinical significance.

RESULTS

C-PCNN showed 85.6% accuracy in diagnosing and identifying anterior horn injury, and 92% accuracy in diagnosing and identifying posterior horn injury. The average accuracy of C-PCNN was 89.8%, AUC = 0.86. The diagnosis accuracy of the attending physician with the aid of the C-PCNN was comparable to that of the chief physician.

CONCLUSION

The C-PCNN-based MRI technique for diagnosing knee meniscus injuries has significant practical value in clinical practice. With a high rate of accuracy, clinical auxiliary physicians can increase the speed and accuracy of diagnosis and decrease the number of incorrect diagnoses.

Serial ultrasonographic imaging can predict failure after meniscus allograft transplantation

Introduction

Treatment monitoring after meniscus allograft transplantation (MAT) is challenging. Ultrasonographic (US) imaging has been proposed as a modality that may allow for treatment monitoring after MAT, but has yet to be clinically validated for this purpose. The objective of this study was to assess the capabilities for serial US imaging during the first year after surgery to predict short-term MAT failure.

Methods

Patients who had undergone Meniscus-only or Meniscus-Tibia MAT for treatment of medial or lateral meniscus deficiency were prospectively evaluated by US imaging at various time points after transplantation. Each meniscus was evaluated for abnormalities in echogenicity, shape, associated effusion, extrusion and extrusion with weightbearing (WB).

Results

Data from 31 patients with a mean follow-up of 32 ± 16 (range, 12-55) months were analysed. MAT failure occurred in 6 patients (19.4%) at a median time point of 20 (range, 14-28) months with 4 (12.9%) converted to total knee arthroplasty. US imaging was effective for assessing MAT extrusion and imaging with WB demonstrated dynamic changes in MAT extrusion. US characteristics that were significantly associated with higher likelihood for MAT failure included abnormal echogenicity, localised effusion, extrusion with WB at 6 months, and localised effusion and extrusion with WB at 1 year.

Conclusions

US assessments of meniscus allografts at 6 months after transplantation can effectively determine risk for short-term failure. Abnormal meniscus echogenicity, persistent localised effusion and extrusion with weightbearing were associated with 8-15 times higher odds for failure, which occurred at a median of 20 months post-transplantation.

Removal of GAGs Regulates Mechanical Properties, Collagen Fiber Formation, and Alignment in Tissue Engineered Meniscus

The complex fibrillar architecture of native meniscus is essential for proper function and difficult to recapitulate in vitro. In the native meniscus, proteoglycan content is low during the development of collagen fibers and progressively increases with aging. In vitro, fibrochondrocytes produce glycosaminoglycans (GAGs) early in culture, in contrast to native tissue, where they are deposited after collagen fibers have formed. This difference in the timing of GAG production hinders the formation of a mature fiber network in such in vitro models. In this study, we removed GAGs from collagen gel-based tissue engineered constructs using chondroitinase ABC (cABC) and evaluated the effect on the formation and alignment of collagen fibers and the subsequent effect on tensile and compressive mechanical properties. Removal of GAGs during maturation of in vitro constructs improved collagen fiber alignment in tissue engineered meniscus constructs. Additionally, removal of GAGs during maturation improved fiber alignment without compromising compressive strength, and this removal improved not only fiber alignment and formation but also tensile properties. The increased fiber organization in cABC-treated groups also appeared to influence the size, shape, and location of defects in these constructs, suggesting that treatment may prevent the propagation of large defects under loading. This data gives another method of modulating the ECM for improved collagen fiber formation and mechanical properties in tissue engineered constructs.

Automatic Detection of Meniscus Tears Using Backbone Convolutional Neural Networks on Knee MRI

BACKGROUND

Timely diagnosis of meniscus injuries is key for preventing knee joint dysfunction and improving patient outcomes because it decreases morbidity and facilitates treatment planning.

PURPOSE

To train and evaluate a deep learning model for automated detection of meniscus tears on knee magnetic resonance imaging (MRI).

STUDY TYPE

Bicentric retrospective study.

SUBJECTS

In total, 584 knee MRI studies, divided among training (n = 234), testing (n = 200), and external validation (n = 150) data sets, were used in this study. The public data set MRNet was used as a second external validation data set to evaluate the performance of the model.

SEQUENCE

A 3 T, coronal, and sagittal images from T1-weighted proton density (PD) fast spin-echo (FSE) with fat saturation and T2-weighted FSE with fat saturation sequences.

ASSESSMENT

The detection system for meniscus tear was based on the improved YOLOv4 model with Darknet-53 as the backbone. The performance of the model was also compared with that of three radiologists of varying levels of experience. The determination of the presence of a meniscus tear from surgery reports was used as the ground truth for the images.

STATISTICAL TESTS

Sensitivity, specificity, prevalence, positive predictive value, negative predictive value, accuracy, and receiver operating characteristic curve were used to evaluate the performance of the detection model. Two-way analysis of variance, Wilcoxon signed-rank test, and Tukey's multiple tests were used to evaluate differences in performance between the model and radiologists.

RESULTS

The overall accuracies for detecting meniscus tears using our model on the internal testing, internal validation, and external validation data sets were 95.4%, 95.8%, and 78.8%, respectively. One radiologist had significantly lower performance than our model in detecting meniscal tears (accuracy: 0.9025 ± 0.093 vs. 0.9580 ± 0.025).

DATA CONCLUSION

The proposed model had high sensitivity, specificity, and accuracy for detecting meniscus tears on knee MRIs.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 2.

Micro RNA in meniscal ailments: current concepts

INTRODUCTION

Micro RNAs (miRNAs) are short non-coding RNAs that act primarily in posttranscriptional gene silencing, and are attracting increasing interest in musculoskeletal conditions.

SOURCE OF DATA

Current scientific literature published in PubMed, Google Scholar, Embase and Web of Science databases.

AREAS OF AGREEMENT

Recently, the potential of miRNAs as biomarkers for diagnosis and treatment of meniscal injuries has been postulated.

AREAS OF CONTROVERSY

Evaluation of the role of miRNAs in patients with meniscal tears is still controversial.

GROWING POINTS

A systematic review was conducted to investigate the potential of miRNA in the diagnosis and management of meniscal damage.

AREAS TIMELY FOR DEVELOPING RESEARCH

Intra-articular injection of microRNA-210 in vivo may represent a potential innovative methodology for the management of meniscal injuries. Characterization of the miRNAs expression in the synovial fluid could lead to the development of better early diagnosis and management strategies for meniscal tears.

Smoking Has No Influence on Outcomes after Repair of the Medial Meniscus in the Hypo and Avascular Zones-A Pilot Study

Complete loss of the meniscus inevitably leads to knee joint degeneration. Smoking is an important factor predicting poor outcome in orthopedics; however, data about its role in meniscus surgery are inconclusive. Smoking could be an important negative factor in isolated meniscus repair. The aim of this paper was to determine the influence of smoking on functional outcomes after isolated all-inside medial meniscus repair. This study included 50 consecutive patients with isolated, traumatic tear of the medial meniscus who underwent knee joint arthroscopy between 2016 and 2019. All-inside arthroscopic repair of the medial meniscus was performed in each case. All patients followed a uniform, postoperative rehabilitation protocol for 8 weeks. The follow-up examination was based on the functional scores at 3 and 6 months postoperatively. According to smoking status there were 17 smokers and 33 non-smokers. The mean number of cigarettes smoked per day was 11, for a mean of 7.4 years, and the mean pack-years index value was 4.9. There was no correlation between smoking years, number of cigarettes smoked per day, pack-years index, and functional outcomes. The arthroscopic inspection of the knee joints revealed cartilage lesions (≤IIº) in eight subjects, suggesting the secondary pathology to the meniscus tear. In this study, we found no evidence of an association between smoking indices and functional outcomes after all-inside repair of chronic medial meniscus tear. The nature of the chronic meniscal tear could be smoking-resistant owing to the poor blood supply to the sites in which these specific lesions occur.

Failure rates and clinical outcomes of synthetic meniscal implants following partial meniscectomy: a systematic review

Background

Meniscal injury is one of the most common indications for knee surgery. The advent of meniscal repair techniques has facilitated meniscal preservation in suitable cases. Meniscal substitution with scaffolds may be advantageous following partial meniscal resection. There are three main scaffolds in current clinical use; Collagen Meniscal Implant (CMI Stryker Corporation, Kalamazoo, MI, USA), Actifit (Actifit, Orteq Ltd, London, UK) and NUsurface (Active Implants, LLC). The purpose of this systematic review was to compare clinical outcomes and failure rates of patients who have had implantation with these meniscal scaffolds.

Methods

MEDLINE and EMBASE databases were searched for studies that included patients who had surgical implantation with Actifit or CMI. Eligibility criteria included papers that described both clinical outcomes and failure rates of these implants, a mean follow up of 5 years and studies published in English. A Google search was also performed to identify any grey literature.

Results

Five Level IV studies were found for Actifit. One Level II, one Level III and four Level IV studies were found for the CMI implant. One Level II study was identified for the NUsurface scaffold with a follow-up 12 months and was included for completeness. Overall, 262 patients were treated with Actifit, 109 with CMI and 65 with NUsurface. Failure rates for Actifit were 18% (range 6.3–31.8%) with a mean follow up of 66.8 months, and for CMI 6.5% (range 0–11.8%) with a mean follow up of 97.1 months. The NUsurface failure rate was 16.9% at 12 months. Clinical outcomes such as VAS, Tegner and Lysholm scores improved significantly post-operatively. However, there was a high volume of concurrent procedures, such as anterior cruciate ligament reconstructions and high tibial osteotomies in each study group; 118 (45%) for Actifit and 53 (45%) for CMI.

Conclusion

The evidence for meniscal scaffold use is insufficient to suggest that they could potentially improve clinical outcomes in patients post-meniscal resection. This is largely due to the high proportion of concurrent procedures performed at index procedure for both CMI and Actifit. On the basis of current evidence, the use of meniscal scaffolds as a sole treatment for partial meniscal defects cannot be recommended, owing to the relatively high failure rate and paucity of clinical data.

The Popliteal Artery is Safe in Medial Meniscal Repair Using All Inside Devices in Adults: An MRI-Based Simulation Study

Introduction

This simulation study on MRI of the knee was performed to assess the risk of injury to the popliteal artery (PA) and common peroneal nerve (CPN) during all-inside meniscal repairs in adults.

Methods

We simulated repair of the posterior horn of both medial (PHMM) and lateral menisci (PHLM) through anteromedial (AM) and anterolateral (AL) portals, using straight and curved devices, on 200 magnetic resonance imaging (MRI) scans taken with the knee in extension. For simulation using straight devices, the shortest distance from the menisco-capsular junction (MCJ) and the free edge of the meniscus to PA and CPN in vectors of AM and AL portals was measured. In curved devices, the closest extracapsular distance from the device tip to PA was measured.

Results

With a straight device through AM portal, the mean distance from the MCJ of PHMM to the PA was 20.7 ± 3.15 mm (13.5-27.4). In PHMM repair through AM portal using a curved device, the mean extracapsular distance from the device tip to PA was 18.8 ± 4 mm (7.7-27.2) while pointing toward and 26 ± 4.5 mm (15.5-35.6) while pointing away from the midline. When using straight devices, the average distance from free edge of LM to PA was 18.5 ± 3.3 mm (9.6-31.2) and from MCJ to PA was 8.9 ± 2.4 mm (3.5-18.8). The average distance measured from the MCJ to CPN through AM and AL portals using straight devices was 19.4 ± 2.8 mm (10.2-32.5) and 22 ± 2.8 mm (10.4-36.7) respectively.

Conclusion

In adults, PA is safe in PHMM repairs using both straight and curved devices irrespective of depth and direction of insertion. In PHLM repairs, the PA is at risk with both straight and curved devices. We recommend adjusting the depth of insertion to as minimum as possible to just penetrate the capsule. The CPN is safe in LM repairs using all-inside devices.

Level of Evidence

Level IV.

Bucket-Handle Meniscus Tear Management With Meniscectomy Versus Repair Correlates With Patient, Socioeconomic, and Hospital Factors

INTRODUCTION

Bucket-handle meniscus tears are common knee injuries that are often treated surgically with meniscectomy or meniscal repair. Although clinical factors may influence the choice of one treatment approach over the other, the influence of patient, socioeconomic, and hospital factors remains poorly characterized. This study aimed to estimate the relative nationwide utilization of these two procedures and delineate a variety of factors that are associated with the selection of one treatment approach over the other.

METHODS

Meniscal repair and meniscectomy procedures conducted for isolated bucket-handle meniscus tears in 2016 and 2017 were identified in the Nationwide Ambulatory Surgery Sample database. Cases were weighted using nationally representative discharge weights. Univariate analyses and a multivariable logistic regression model were used to compare patient, socioeconomic, and hospital factors associated with meniscal repair versus meniscectomy.

RESULTS

In total, 12,239 cases were identified, which represented 17,236 cases after weighting. Of these, meniscal repair was conducted for 4,138 (24.0%). Based on the logistic regression model, meniscal repair was less likely for older and sicker patients. By contrast, several factors were associated with markedly higher odds of undergoing meniscal repair compared with meniscectomy. These included urban teaching hospitals; geographic location in the midwest, south, and west; and higher median household income.

DISCUSSION

Using a large nationally representative cohort, the current data revealed that only 24.0% of surgically treated bucket-handle meniscus tears were treated using repair. Identification of patient, socioeconomic, and hospital factors differentially associated with meniscal repair suggest that other factors may systematically influence surgical decision-making for this patient population. Surgeons should be conscious of these potential healthcare disparities when determining the optimal treatment for their patients.

LEVEL OF EVIDENCE

Level III.

Strain-Dependent Diffusivity of Small and Large Molecules in Meniscus

Due to lack of full vascularization, the meniscus relies on diffusion through the extracellular matrix to deliver small (e.g., nutrients) and large (e.g., proteins) to resident cells. Under normal physiological conditions, the meniscus undergoes up to 20% compressive strains. While previous studies characterized solute diffusivity in the uncompressed meniscus, to date, little is known about the diffusive transport under physiological strain levels. This information is crucial to fully understand the pathophysiology of the meniscus. The objective of this study was to investigate strain-dependent diffusive properties of the meniscus fibrocartilage. Tissue samples were harvested from the central portion of porcine medial menisci and tested via fluorescence recovery after photobleaching to measure diffusivity of fluorescein (332 Da) and 40 K Da dextran (D40K) under 0%, 10%, and 20% compressive strain. Specifically, average diffusion coefficient and anisotropic ratio, defined as the ratio of the diffusion coefficient in the direction of the tissue collagen fibers to that orthogonal, were determined. For all the experimental conditions investigated, fluorescein diffusivity was statistically faster than that of D40K. Also, for both molecules, diffusion coefficients significantly decreased, up to ∼45%, as the strain increased. In contrast, the anisotropic ratios of both molecules were similar and not affected by the strain applied to the tissue. This suggests that compressive strains used in this study did not alter the diffusive pathways in the meniscus. Our findings provide new knowledge on the transport properties of the meniscus fibrocartilage that can be leveraged to further understand tissue pathophysiology and approaches to tissue restoration.

Repair of a Horizontal Cleavage Tear of the Lateral Meniscus with Circumferential Compression Stitches and Marrow Venting Augmentation

Horizontal cleavage tears (HCTs) are challenging meniscal tear patterns, as they split the meniscus into inferior and superior leaflets, while also involving the central, less vascular portions of the meniscus. Circumferential compression sutures using an all-inside self-retrieving suture passing device like the Novostitch Pro (Smith & Nephew, Andover, MA) have demonstrated the ability to create stable repair constructs with uniform compression across both leaflets in the setting of HCTs. Additionally, biological augmentation of meniscal repairs using a marrow venting procedure (MVP) has demonstrated superior clinical outcomes relative to isolated meniscal repairs. Thus, the purpose of this technical note is to outline our procedure for implementing circumferential compression sutures and biologic augmentation using an MVP for repairing an HCT of the lateral meniscus.

The Effects of Korean Medicine Treatment for Meniscus Tears: A Retrospective Chart Review

Changes in symptoms and dysfunction related to meniscus tears following the use of Korean medicine for ≥ 4 days were studied. The medical charts of 53 cases of diagnosed meniscus tears (magnetic resonance imaging) with an admission Numeric Rating Scale (NRS) score ≥ 4, between 2017 and 2022 were retrospectively reviewed. Treatments included acupuncture, pharmacopuncture, herbal treatment, Chuna therapy, and physiotherapy. The NRS, Western Ontario and McMaster Universities Osteoarthritis Index, and European Quality of Life 5 Dimensions were performed at admission and discharge. There were 42 females and 11 males in this study. Patients were more likely to be in their 60s (38.18%), have an unknown etiology (81.13%), and have complex tears (50.94%). After receiving a combination of alternative Korean medicine during hospitalization, the mean NRS score improved from 6.82 ± 1.19 to 3.66 ± 1.83 (p < 0.001), the Western Ontario and McMaster Universities Osteoarthritis Index score improved from 46.47 ± 20.99 to 37.98 ± 19.23 (p < 0.001), and the mean European Quality of Life Five Dimensions score improved from 0.61 ± 0.18 to 0.68 ± 0.14 (p < 0.001) after treatment. These results suggest that Korean medicine treatment of meniscus tears alleviated pain and improved physical function.