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PloS One 2021Meniscus tears of the knee are among the most common orthopedic knee injury. Specifically, tears of the posterior root can result in abnormal meniscal extrusion leading...
Meniscus tears of the knee are among the most common orthopedic knee injury. Specifically, tears of the posterior root can result in abnormal meniscal extrusion leading to decreased function and progressive osteoarthritis. Despite contemporary surgical treatments of posterior meniscus root tears, there is a low rate of healing and an incidence of residual meniscus extrusion approaching 30%, illustrating an inability to recapitulate native meniscus function. Here, we characterized the differential functional behavior of the medial and lateral meniscus during axial compression load and dynamic knee motion using a cadaveric model. We hypothesized essential differences in extrusion between the medial and lateral meniscus in response to axial compression and knee range of motion. We found no differences in the amount of meniscus extrusion between the medial and lateral meniscus with a competent posterior root (0.338mm vs. 0.235mm; p-value = 0.181). However, posterior root detachment resulted in a consistently increased meniscus extrusion for the medial meniscus compared to the lateral meniscus (2.233mm vs. 0.4705mm; p-value < 0.0001). Moreover, detachment of the posterior root of the medial meniscus resulted in an increase in extrusion at all angles of knee flexion and was most pronounced (4.00mm ± 1.26mm) at 30-degrees of knee flexion. In contrast, the maximum mean extrusion of the lateral meniscus was 1.65mm ± 0.97mm, occurring in full extension. Furthermore, only the medial meniscus extruded during dynamic knee flexion after posterior root detachment. Given the differential functional behaviors between the medial and lateral meniscus, these findings suggest that posterior root repair requires reducing overall meniscus extrusion and recapitulating the native functional responses specific to each meniscus.
Topics: Humans; Knee Injuries; Knee Joint; Lower Extremity; Menisci, Tibial; Meniscus; Range of Motion, Articular
PubMed: 34758053
DOI: 10.1371/journal.pone.0259678 -
Journal of Orthopaedic Surgery and... Mar 2022The indications and efficacy after arthroscopic partial meniscectomy (APM) for degenerative medial meniscus lesions (DMMLs) have been controversial. The purpose of this...
BACKGROUND
The indications and efficacy after arthroscopic partial meniscectomy (APM) for degenerative medial meniscus lesions (DMMLs) have been controversial. The purpose of this study was to identify predictors of unfavorable clinical and radiologic outcomes after APM for DMMLs and to choose appropriate indications and improve treatment efficacy.
METHODS
A total of 86 patients with DMMLs undergoing APM were retrospectively reviewed. The mean follow-up time was 32.1 months. Clinical outcomes (including Lysholm score) and radiographic results (including Kellgren-Lawrence grade (K-L grade: 0/1/2/3/4) were evaluated at preoperative and final follow-up. Preoperative prognostic factors, including gender, age, Body Mass Index (BMI), Hip-Knee-Ankle (HKA), Medial Posterior Tibial Slope (MPTS), Medial Meniscus Extrusion (MME), K-L grade, occupational kneeling, and cartilaginous condition (Outerbridge grade ≤ 2, VS ≥ 3), for relatively unfavorable (fair or poor grade) Lysholm and progression of K-L grade, were investigated by multivariate logistic regression analysis. Receiver operating characteristic curve was used to identify a cutoff point for the extent of medial meniscal extrusion that was associated with the final Lysholm score.
RESULTS
A significantly improved postoperative Lysholm score (84.5 ± 9.7) compared with the preoperative score (63.8 ± 9.3) (P < 0.001), but a progression of K-L grade (20/36/30/0/0-15/27/25/19/0) (P < 0.001). The adverse prognostic factor of Lysholm score was the advancing age (OR 1.109, P = 0.05) and HKA (OR 0.255, P < 0.001). The adverse prognostic factor of K-L grade progression was MME (OR 10.327, P < 0.001). The cutoff point for the relative value of preoperative medial meniscal extrusion associated with relatively unfavorable Lysholm scores was 2.05 mm (Area = 0.8668, P value < 0.0001, Sensitivity = 62.16%, Specificity = 93.88%).
CONCLUSIONS
Clinically, varus alignment, large MME, and older age were found to predict a poor prognosis after APM for DMMLs. The preoperative extent of MME can be used as a predictive factor for osteoarthritis in APM. Patients with varus and MME should avoid APM. High tibial osteotomy may be an effective treatment strategy.
Topics: Aged; Arthroscopes; Female; Humans; Male; Meniscectomy; Menisci, Tibial; Middle Aged; Prognosis; Retrospective Studies; Tibial Meniscus Injuries
PubMed: 35303914
DOI: 10.1186/s13018-022-03045-0 -
Knee Surgery, Sports Traumatology,... Apr 2021Contralateral medial meniscus posterior root tear (MMPRT) can sometimes occur after primary surgeries for MMPRT and lead to unsatisfactory outcomes. The incidence rate...
PURPOSE
Contralateral medial meniscus posterior root tear (MMPRT) can sometimes occur after primary surgeries for MMPRT and lead to unsatisfactory outcomes. The incidence rate and risk factors for contralateral MMPRT have not been well investigated, despite their clinical importance. Therefore, the incidence and predictors of bilateral MMPRT were aimed to be evaluated.
METHODS
Fourteen patients with bilateral MMPRT (group B) and 169 patients with unilateral MMPRT (group U) were enrolled in this study. Sex, age, body mass index, time between injury and surgery, and medial tibial slope angle (MTSA) were compared between the groups. MTSA was measured using lateral radiographs.
RESULTS
The incidence rate of bilateral MMPRT was 6.2% among all patients with MMPRTs. Multivariate logistic regression analysis showed that a prolonged time between injury and surgery (odds ratio [OR], 1.0; 95% confidence interval [CI] 1.00-1.01; P < 0.05) and steeper MTSA (OR, 1.85; 95% CI 1.21-2.64; P < 0.01) were significantly associated with the development of bilateral MMPRT. Receiver operating characteristic curve analysis showed that MTSA > 10.0° was associated with bilateral MMPRT, with a sensitivity of 93% and specificity of 69%.
CONCLUSION
A longer time between injury and surgery and steeper MTSA were risk factors for the development of bilateral MMPRT. Surgeons need to pay close attention to the contralateral knee in addition to the primary injured knees when treating knees with steep MTSA. Besides, early meniscal repair of primary MMPRT would be important to prevent the events of contralateral MMPRT.
LEVEL OF EVIDENCE
III.
Topics: Aged; Female; Humans; Incidence; Knee Injuries; Logistic Models; Magnetic Resonance Imaging; Male; Menisci, Tibial; Middle Aged; ROC Curve; Radiography; Retrospective Studies; Risk Factors; Rupture; Sensitivity and Specificity; Tibia; Tibial Meniscus Injuries
PubMed: 32488369
DOI: 10.1007/s00167-020-06079-1 -
Cartilage Dec 2021Meniscus injury and the hypoxia-inducible factor (HIF) pathway are independently linked to osteoarthritis pathogenesis, but the role of the meniscus HIF pathway remains...
OBJECTIVE
Meniscus injury and the hypoxia-inducible factor (HIF) pathway are independently linked to osteoarthritis pathogenesis, but the role of the meniscus HIF pathway remains unclear. We sought to identify and evaluate HIF pathway response in normal and osteoarthritic meniscus and to examine the effects of Epas1 (HIF-2α) insufficiency in mice on early osteoarthritis development.
METHODS
Normal and osteoarthritic human meniscus specimens were obtained and used for immunohistochemical evaluation and cell culture studies for the HIF pathway. Meniscus cells were treated with pro-inflammatory stimuli, including interleukins (IL)-1β, IL-6, transforming growth factor (TGF)-α, and fibronectin fragments (FnF). Target genes were also evaluated with HIF-1α and HIF-2α (Epas1) overexpression and knockdown. Wild-type ( = 36) and Epas1 ( = 30) heterozygous mice underwent destabilization of the medial meniscus (DMM) surgery and were evaluated at 2 and 4 weeks postoperatively for osteoarthritis development using histology.
RESULTS
HIF-1α and HIF-2α immunostaining and gene expression did not differ between normal and osteoarthritic meniscus. While pro-inflammatory stimulation significantly increased both catabolic and anabolic gene expression in the meniscus, HIF-1α and Epas1 expression levels were not significantly altered. Epas1 overexpression significantly increased Col2a1 expression. Both wild-type and Epas1 mice developed osteoarthritis following DMM surgery. There were no significant differences between genotypes at either time point.
CONCLUSION
The HIF pathway is likely not responsible for osteoarthritic changes in the human meniscus. Additionally, Epas1 insufficiency does not protect against osteoarthritis development in the mouse at early time points after DMM surgery. The HIF pathway may be more important for protection against catabolic stress.
Topics: Animals; Chondrocytes; Hypoxia; Menisci, Tibial; Meniscus; Mice; Osteoarthritis
PubMed: 32940061
DOI: 10.1177/1947603520958143 -
Journal of Orthopaedic Research :... Jun 2018The dog has been used extensively as an experimental model to study meniscal treatments such as meniscectomy, meniscal repair, transplantation, and regeneration....
The dog has been used extensively as an experimental model to study meniscal treatments such as meniscectomy, meniscal repair, transplantation, and regeneration. However, there is very little information on meniscal kinematics in the dog. This study used MR imaging to quantify in vitro meniscal kinematics in loaded dog knees in four distinct poses: extension, flexion, internal, and external rotation. A new method was used to track the meniscal poses along the convex and posteriorly tilted tibial plateau. Meniscal displacements were large, displacing 13.5 and 13.7 mm posteriorly on average for the lateral and medial menisci during flexion (p = 0.90). The medial anterior horn and lateral posterior horns were the most mobile structures, showing average translations of 15.9 and 15.1 mm, respectively. Canine menisci are highly mobile and exhibit movements that correlate closely with the relative tibiofemoral positions. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1710-1716, 2018.
Topics: Animals; Biomechanical Phenomena; Dogs; Magnetic Resonance Imaging; Menisci, Tibial; Movement
PubMed: 29106743
DOI: 10.1002/jor.23800 -
BMC Musculoskeletal Disorders Sep 2021Anatomical variations of the attachment of medial meniscus are a common finding. However, anomalies of the posterior horn are extremely rare. Only two cases of posterior...
BACKGROUND
Anatomical variations of the attachment of medial meniscus are a common finding. However, anomalies of the posterior horn are extremely rare. Only two cases of posterior root anomaly have been described prior to the routine use of arthroscopy for evaluation and treatment of meniscal pathology. In this report, we present an anomaly of both the anterior and posterior roots of the medial meniscus that posed both a diagnostic and therapeutic dilemma.
CASE PRESENTATION
The patient is young male soccer player who is currently 16 years of age and began having the atraumatic onset of pain and symptoms that limited performance starting at age 14 and was referred for failure of response to nonoperative treatment. Diagnostic arthroscopy revealed the presence of an anteromedial meniscofemoral ligament whereas the posterior root showed no bony attachment. The radiographic and arthroscopic findings are described. The clinical decision was made after to proceed with observation, reassurance, and gradual return to full activity with physiotherapy guidance.
DISCUSSION AND CONCLUSION
The absence of injury, the mild complaints reported by the patient, his age, skeletal immaturity, and remaining growth led us to adopt a conservative approach to treating this anatomic variant and currently the patient is able to participate fully in sports without symptoms or restrictions.
Topics: Adolescent; Arthroscopy; Humans; Knee Joint; Ligaments, Articular; Male; Menisci, Tibial
PubMed: 34560880
DOI: 10.1186/s12891-021-04696-6 -
International Journal of Environmental... Dec 2022Complete loss of the meniscus inevitably leads to knee joint degeneration. Smoking is an important factor predicting poor outcome in orthopedics; however, data about its...
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.
Topics: Humans; Menisci, Tibial; Tibial Meniscus Injuries; Pilot Projects; Arthroscopy; Rupture; Smoking; Retrospective Studies
PubMed: 36498202
DOI: 10.3390/ijerph192316127 -
Journal of the Mechanical Behavior of... Sep 2022The mechanical wear and tear of soft connective tissue from repetitive joint loading is a primary factor in degenerative joint disease, and therefore methods are needed...
The mechanical wear and tear of soft connective tissue from repetitive joint loading is a primary factor in degenerative joint disease, and therefore methods are needed to accurately characterize wear in joint structures. Here, we evaluate the accuracy of using a structured light 3D optical scanning system and modeling software to quantify and visualize volume loss in whole human meniscus subjected to in vitro joint loading. Using 3D printed meniscus replicas with known wear volumes, we determined that this novel imaging method has a mean accuracy of approximately 13 mm, corresponding to a mean error of less than 7% when measuring meniscal volumetric changes of 0.2 cm (size of a pea). The imaging method was then applied to measure the in vitro wear of whole human menisci at four time points when a single cadaveric knee was subjected to one million cycles of controlled joint loading. The medial and lateral menisci reached steady state volumetric reductions of 0.72 cm and 0.34 cm per million cycles, respectively. Colorimetric maps of linear wear depth revealed high wear and deformation in the posterior regions of both the medial and lateral menisci. For the first time, this study has developed a method to accurately characterize volume loss in whole meniscus subjected to in vitro joint loading. This 3D scanning method offers researchers a new investigative tool to study mechanical wear and joint degeneration in meniscus, and other soft connective tissues.
Topics: Humans; Knee; Knee Joint; Menisci, Tibial; Meniscus; Tibial Meniscus Injuries
PubMed: 35834895
DOI: 10.1016/j.jmbbm.2022.105338 -
Acta Medica Okayama Apr 2022Bone marrow edema (BME) after meniscus injury and risk factors for subchondral insufficiency fracture of the knee (SIFK) have been reported. However, their association...
Grade of Subchondral Insufficiency Fracture of the Knee and the Presence of a Posterior Shiny-Corner Lesion are Correlated with Duration of Medial Meniscus Posterior Root Tear in Women.
Bone marrow edema (BME) after meniscus injury and risk factors for subchondral insufficiency fracture of the knee (SIFK) have been reported. However, their association with medial meniscus posterior root tear (MMPRT) remains unknown. We investigated the association of BME volume (BME-V), posterior shinycorner lesion (PSCL), and SIFK with MMPRT to examine the correlations between BME-V and medial meniscus extrusion (MME), PSCL and duration from injury to the time of magnetic resonance imaging (duration), and SIFK and duration. Twenty-nine patients who underwent surgery for MMPRT were included (mean age, 59.2; range, 39-84). The presence of PSCL, femoral BME-V (cm3), and SIFK grade (1-4) were evaluated. Preoperative factors, such as MME (mm) and duration (weeks), were investigated using multivariate linear/ logistic regression analyses. Multivariate linear regression analysis revealed duration as a significant factor for high-grade SIFK (p<0.01). Multivariate logistic regression analysis revealed duration as a significant factor for the presence of PSCL (odds ratio=0.94, p<0.05). A long duration of MMPRT leads to severe MME and highgrade SIFK (3 and 4), often resulting in knee arthroplasty. Early diagnosis of MMPRT and pullout repair can prevent severe MME and high-grade SIFK.
Topics: Female; Fractures, Stress; Humans; Knee Injuries; Knee Joint; Magnetic Resonance Imaging; Menisci, Tibial; Middle Aged; Retrospective Studies; Rupture; Tibial Meniscus Injuries
PubMed: 35503439
DOI: 10.18926/AMO/63405 -
Journal of Orthopaedic Science :... Mar 2021Many histological, mechanical, and clinical studies have been performed on the medial meniscus posterior root attachment, as it often tears in patients with...
BACKGROUND
Many histological, mechanical, and clinical studies have been performed on the medial meniscus posterior root attachment, as it often tears in patients with osteoarthritic knee. Medial meniscal root repair is recommended in clinical situations; however, to date, no studies have examined the differences between meniscal root and horn cells. The aim of this study was, therefore, to investigate the morphology, reaction to cyclic tensile strain, and gene expression levels of medial meniscal root and horn cells.
METHODS
Meniscal samples were obtained from the medial knee compartments of 10 patients with osteoarthritis who underwent total knee arthroplasty. Root and horn cells were cultured in Dulbecco's modified Eagle's medium without enzymes. The morphology, distribution, and proliferation of medial meniscal root and horn cells, as well as the gene and protein expression levels of Sry-type HMG box 9 and type II collagen, were determined after cyclic tensile strain treatment.
RESULTS
Horn cells had a triangular morphology, whereas root cells were fibroblast-like. The number of horn cells positive for Sry-type HMG box 9 and type II collagen was considerably higher than that of root cells. Although root and horn cells showed similar levels of proliferation after 48, 72, or 96 h of culture, more horn cells than root cells were lost following a 2-h treatment with 5% and 10% cyclic tensile. Sry-type HMG box 9 and α1(II) collagen mRNA expression levels were significantly enhanced in both cells after 2- and 4-h cyclic tensile strain (5%) treatment.
CONCLUSIONS
Medial meniscal root and horn cells have distinct morphologies, reactions to mechanical stress, and cellular phenotypes. Our results suggest that physiological tensile strain is important to activate extracellular matrix production in horn cells.
Topics: Arthroplasty, Replacement, Knee; Humans; Knee Joint; Menisci, Tibial; Stress, Mechanical; Tibial Meniscus Injuries
PubMed: 32223991
DOI: 10.1016/j.jos.2020.02.015