Medial Meniscal Root Tears Research Articles

Comparative study between isolated medial meniscus root repair versus open-wedge high tibial osteotomy versus combined approach in patients with root tears, 2-year follow-up

Background Medial meniscus root tears usually lead to loss of hoop tension of the meniscus and result in high-contact pressure in the medial compartment of the knee. Surgical management of those types of tears is mandatory to restore hope tension and to save medial compartment. This study was done to evaluate the necessity of medial root repair with high tibial osteotomy (HTO) for treatment of medial meniscus root tears. Patients and methods This is a prospective comparative study over 60 patients with medial meniscal root tears. The patients were classified randomly into three groups. The first group (group A) was treated with isolated medial meniscus posterior root tear repair (n=20). The second group (group B) was treated with isolated open-wedge high HTO (n=20). The third group (group C) was treated using combined medial meniscal root repair with high tibial open-wedge osteotomy (n=20). A clinical evaluation was made using range of motion (ROM) and pain assessment. Functional evaluation was done using Lysholm score and Hospital for Special Surgery score. Radiological evaluation was done using follow-up standing Lyon–Schuss films. Results Regarding the patients’ reported outcome measures, one-way analysis of variance was calculated to compare means between the three groups. The results of isolated root repair were the worst and there was no statistically significant difference between groups B and C. Conclusion Results recommend isolated HTO as a solo fast-attack procedure with reliable durable clinical and radiological outcomes for the treatment of root tears of the posterior horn of the medial meniscus.

Meniscus Injury and its Surgical Treatment Does not Increase Initial Whole Knee Joint Friction.

While it is generally accepted that traumatic meniscus pathologies lead to degenerative articular cartilage changes in the mid-to long-term and consecutively to post-traumatic osteoarthritis (PTOA), very little is known about how such injuries initiate tribological changes within the knee and their possible impact on PTOA acceleration. Therefore, the aim of this study was to investigate the influence of three different medial meniscus states (intact, posterior root tear, total meniscectomy) on the initial whole knee joint friction. Six ovine knee joints were tested in a passive pendulum friction testing device under an axial load of 250 N and an initial deflection of 12°, representing swing phase conditions, and under an axial load of 1000 N and an initial deflection of 5°, simulating stance phase conditions. To additionally consider the influence of the time-dependent viscoelastic nature of the knee joint soft tissues on whole joint friction, the tests were performed twice, directly following load application and after 20 min creep loading of either 250 N or 1000 N axial load. On the basis of a three-dimensional joint kinematic analysis, the energy loss during the passive joint motion was analyzed, which allowed considerations on frictional and damping processes within the joint. The so-called “whole knee joint” friction was evaluated using the boundary friction model from Stanton and a viscous friction model from Crisco et al., both analyzing the passive joint flexion-extension motion in the sagittal plane. Significantly lower friction coefficients were observed in the simulated swing phase after meniscectomy (p < 0.05) compared to the intact state. No initial whole joint friction differences between the three meniscus states (p > 0.05) were found under stance phase conditions. Soft tissue creeping significantly increased all the determined friction coefficients (p < 0.05) after resting under load for 20 min. The exponential decay function of the viscous friction model provided a better fit (R 2∼0.99) to the decaying flexion-extension data than the linear decay function of the boundary friction model (R 2∼0.60). In conclusion, this tribological in vitro study on ovine knee joints indicated that neither a simulated posterior medial meniscus root tear nor the removal of the medial meniscus resulted in an initially increased whole joint friction.

Meniscal Root Repair

Background: Meniscal root tears typically result from a hyperflexion/squatting injury or are in conjunction with ligamentous knee injury. Once a complete tear occurs, the meniscus is unable to convert axial loads to transverse hoop stresses which result in increased tibiofemoral contact pressure and osteoarthritis. The goal of a meniscal root repair is to anatomically reattach the meniscal root to the tibia plateau. Complete and partial healing occurs in over 93% of cases with retear rates ranging from 0% to 7%. Indications: We present a case of a highly active 21-year-old male collegiate soccer play that sustained a medial meniscal root tear after slipping on ice. Technique: An anatomic medial meniscal root repair was performed using a transtibial guide and 2 loop sutures tied over a button. Results: Full anatomic footprint coverage was able to be achieved intraoperatively and gentle range of motion from 0 to 90° of flexion did not result in gap formation. Discussion/Conclusion: Successful outcomes with full anatomic footprint coverage of the medial meniscal root can be achieved with 2-loop suture button configuration.

ICRS scores worsen between 2-year short term and 5-year mid-term follow-up after transtibial medial meniscus root repair despite maintained functional outcomes.

The purpose of this study was to evaluate the mid-term results of posterior medial meniscal root tear (PMMRT) repair through assessment of functional outcome scores and magnetic resonance imaging (MRI). This was a single-center, retrospective study evaluating patients that had undergone a PMMRT. This was a follow-up to a previously published 2-year outcome study (all original patients were invited to participate). Clinical outcomes included pre- and postoperative International Knee Documentation Committee (IKDC) and Lysholm scores. Root healing, meniscal extrusion, and cartilage degeneration via International Cartilage Repair Society Scale (ICRS) grades were assessed on MRI by two musculoskeletal fellowship-trained radiologists. 10 of the original study's 18 patients were able to participate. Mean age and BMI was 48.4 ± 12.0years and 29.5 ± 4.5, respectively, with mean follow-up 65.5 ± 8.3months (range 52.0-75.8) (60% female). The IKDC significantly increased from 43 ± 13 preoperatively to 75 ± 16 at 5-year follow-up (p < 0.001). There was no significant change in IKDC score between 2-year and 5-year follow-up [75 ± 16 vs 73 ± 20, (n.s)]. TheLysholm also significantly increased between preoperative and 5-year follow-up (49 ± 7 vs 84 ± 11, p < 0.001). There was no significant change between Lysholm score at 2-year and 5-year follow-up [84.0 ± 11 vs 82 ± 13, (n.s)]. Mean extrusion did not significantly change from the preoperative state to 5-year follow-up [4.80mm ± 1.9 vs 5.0mm ± 2.5, (n.s.)]. Extrusion also did not significantly change between 2-and 5-year follow-up [6.1 ± 3.2mm vs 5.0mm ± 2.5, (n.s.)]. No patients with > 3mm of extrusion on preoperative MRI had < 3mm of extrusion on postoperative MRI. Both medial femoral condyle and medial tibial plateau ICRS grades significantly increased from preoperative to 2-year follow-up (p = 0.038, p = 0.023, respectively). Medial femoral condyle and medial tibial plateau ICRS grades again significantly increased between 2-year and 5-year follow-up (p = 0.014, p = 0.034). Patients treated with the transtibial suture pullout technique with two locking cinch sutures had maintenance of clinical outcome improvements at 5-year follow-up. However, extrusion was widely prevalent,with worsening progression of femoral and tibial chondral disease. Level 4.

Meniscal Root Repair in Pediatric Patients: Minimum 2-Year Outcomes (196)

Objectives:The medial and lateral menisci function to optimize force transmission across the knee by increasing contact area between the femur and tibia, absorbing shock, and transmitting loads. The anterior and posterior meniscus roots anchor the meniscus to bone. Injuries to the meniscus root attachments result in extrusion of the meniscus, impaired distribution of hoop stresses, and progressive degenerative articular wear. As a result of these deleterious effects, there has been increasing emphasis on repair of meniscus root injuries to restore structure and function. The purpose of this study is to describe meniscus root tears, associated injuries, and minimum 2-year treatment outcomes in a series of pediatric patients.Methods:A single-institution, IRB approved, retrospective review was performed of consecutive pediatric patients less than 19 years of age with a meniscus root tear treated with transosseous root repair over a 4-year period. All patients had minimum 24-month clinical follow-up. Partial root tears treated with partial meniscectomy or irreparable root tears were excluded. All meniscus root tears were classified arthroscopically based on the tear types described by LaPradeADDIN EN.CITE 9. The primary outcomes were revision meniscus surgery and patient reported outcome scores (PROs) (Lysholm, Patient Satisfaction, and Tegner activity).Results:Twenty-one patients, 11 males and 10 females with a mean age of 15 years (range 7 – 18 years), met inclusion criteria. There were 15 lateral meniscus root tears and 6 medial meniscus root tears. The tears occurred in the posterior root in 20 patients (95%). The most common injury pattern was a lateral meniscus posterior root tear (14 patients, 67%). 18 patients (86%) had an associated ligament tear: 13 ACL tears and 5 PCL tears. Two root tears occurred in isolation, and both were the posterior root of the medial meniscus. The majority of meniscus root tears (15 patients, 71%) were root avulsions (type 5). Mean follow-up was 42 months (range 25 – 71 months). Three patients had a second surgery on the affected knee. In two patients, one with revision ACL reconstruction and one treated with chondroplasty of the patella, the meniscus root repair was noted to be well healed. A third patient sustained a new injury to the knee 4 years following medial meniscus posterior root repair and underwent partial medial meniscectomy. At final follow-up, PROs were obtained for 17 patients (81%). Mean Lysholm score was 91 (range 51 – 100). Mean patient satisfaction score was 8.7 (range 5 – 10). Fourteen of 16 patients (88%) reported returning to the same or higher level of activity following surgery.Conclusions:Meniscus root tears occur in pediatric patients, most commonly as root avulsions of the posterior root of the lateral meniscus and in association with ACL tears. This is unique as compared to the adult population, in which the medial meniscus posterior root is often injured in isolation and radial tears adjacent the root are the most commonly described injury pattern. In our case series, transosseous root repair resulted in successful outcomes in the majority of patients with durable results at midterm follow-up.

The Natural History of Medial Meniscal Root Tears: A Biomechanical and Clinical Case Perspective.

Posterior medial meniscus root tears (PMMRTs) make up a relatively notable proportion of all meniscus pathology and have been definitively linked to the progression of osteoarthritis (OA). While known risk factors for development of OA in the knee include abnormal tibial coronal alignment, obesity and female gender, PMMRTs have emerged in recent years as another significant driver of degenerative disease. These injuries lead to an increase in average contact pressure in the medial compartment, along with increases in peak contact pressure and a decrease in contact area relative to the intact state. Loss of the root attachment impairs the function of the entire meniscus and leads to meniscal extrusion, thus impairing the force-dissipating role of the meniscus. Anatomic meniscus root repairs with a transtibial pullout technique have been shown biomechanically to restore mean and peak contact pressures in the medial compartment. However, nonanatomic root repairs have been reported to be ineffective at restoring joint pressures back to normal. Meniscal extrusion is often a consequence of nonanatomic repair and is correlated with progression of OA. In this study, the authors will describe the biomechanical basis of the natural history of medial meniscal root tears and will support the biomechanical studies with a case series including patients that either underwent non-operative treatment (5 patients) or non-anatomic repair of their medial meniscal root tears (6 patients). Using measurements derived from axial MRI, the authors will detail the distance from native root attachment center of the non-anatomic tunnels and discuss the ongoing symptoms of those patients. Imaging and OA progression among patients who were treated nonoperatively before presentation to the authors will be discussed as well. The case series thus presented will illustrate the natural history of meniscal root tears, the consequences of non-anatomic repair, and the findings of symptomatic meniscal extrusion associated with a non-anatomic repair position of the meniscus.

Effect of concurrent repair of medial meniscal posterior root tears during high tibial osteotomy for medial osteoarthritis during short-term follow-up: a systematic review and meta-analysis

BackgroundMedial meniscal posterior root tears (MMPRTs) are frequently associated with medial compartment osteoarthritis, leading to loss of meniscal hoop tension. This study aimed to evaluate the efficacy of concurrent MMPRT repair during high tibial osteotomy (HTO) compared to HTO alone in patients with medial osteoarthritis and MMPRTs.MethodsThe MEDLINE/PubMed, EMBASE, and Cochrane Library databases were searched for studies reporting on concurrent MMPRT repair during HTO. Pre- and postoperative data were pooled to investigate the treatment effects of concurrent MMPRT repair during HTO, and compare postoperative clinical, radiological, and arthroscopic outcomes including cartilage status and healing event rates according to the arthroscopic classification of MMPRT healing (complete, partial [lax or scar tissue], or failed healing) between HTO patients with and without concurrent MMPRT repair. The random-effect model was used to pool the standardized mean differences, odds ratios (ORs), 95% confidence intervals (CIs), and event rates.ResultsSeven patient subgroups in six articles divided according to meniscal repair techniques were included in the final analysis. Concurrent MMPRT repair during HTO significantly improved the Lysholm score, while no intergroup differences were observed in the postoperative Lysholm and WOMAC scores, as well as radiological and arthroscopic outcomes. Those who underwent concurrent MMPRT repair showed a higher rate of complete meniscal healing (OR: 4.792, 95% CI, 1.95–11.79), with a pooled rate of complete meniscal healing of 0.327 (95% CI, 0.19–0.46).ConclusionConcurrent MMPRT repair during HTO for medial osteoarthritis with MMPRTs has little benefits on the clinical, radiological, and arthroscopic outcomes during short-term follow-up. Further accumulation of evidence is needed for long-term effects.

Functional outcome of medial meniscus root repair in medial compartment osteoarthritic knee and it’s correlation with preexisting comorbidities

Objective: The knee joint is one of the most commonly affected joints of the body and this can be attributed to its exposure to external forces and the high functional demands placed on the joint. Meniscal root tears have conventionally been treated with menisectomy and in this study we evaluate the effects of repairing the torn posterior medial meniscal root. We also study the effects of age and body mass index on the postoperative outcome of the patient. Methods: 35 patients with posterior horn medial meniscus root tear were operated with root repair with either a fibre wire/ fibre tape or their pre and post-operative tegner lysholm scores were evaluated. Results and Conclusions: The evaluation was suggestive that medial meniscus root repair improved outcomes. Additionally, a relationship was established between the body mass index and patient age with that of the post-operative function.

Investigating the Chronology of Meniscus Root Tears: Do Medial Meniscus Posterior Root Tears Cause Extrusion or the Other Way Around?

Objectives:Meniscus root tears are increasingly being recognized. Meniscus extrusion has previously been associated with medial root tears; however, the relationship between secondary meniscus restraints, such as the meniscotibial (MT) ligament, extrusion, and root tears has yet to be formally evaluated. The purpose of this study was to better understand the association between MT ligament competence, medial meniscus extrusion, and medial meniscus posterior root tears (MMPRT), as well as to determine the progression of meniscus extrusion over time.Methods:Serial MRI’s from our institution were reviewed for patients who showed evidence of medial meniscus extrusion and MMPRT on at least one of 2+ available MRI’s. All patients were symptomatic at the time of diagnosis. All MRI’s were analyzed independently by two board-certified musculoskeletal radiologists. MT ligament disruption, medial meniscus extrusion, and MMPRT presence was recorded for each MRI. The time between MRI’s, presence of insufficiency fractures, and Outerbridge classification for the medial femur and tibia were also evaluated.Results:27 knees in 26 patients were included in this study, with a total of 63 MRI’s analyzed (21 knees with 2 MRI’s, 3 with 3 MRI’s, and 3 with 4 MRI’s). All patients demonstrated clear medial meniscus extrusion and meniscotibial ligament disruption prior to the subsequent development of MMPRTs (p < 0.001). Mean extrusion at the time of initial MRI was 3.3 ± 1.1 mm, and increased significantly to 5.5 ± 1.8 mm at the time of first imaging with an identified MMPRT (p < 0.001). The average time between initial MRI and the first identification of MMPRT on a later MRI was 1.7 ± 1.6 years.Conclusions:In a sample of 27 symptomatic knees with serial MRI’s both before and after MMPRT diagnosis, all patients demonstrated MT ligament disruption and associated meniscus extrusion prior to the development of subsequent medial meniscus root tears. These findings suggest that MT ligament disruption and medial meniscus extrusion represent early and predisposing events contributing to MMPRT. Therefore, this provides a possible explanation of why meniscus extrusion is not corrected with medial meniscus root repair.

MAGNETIC RESONANCE IMAGING OF LATERAL MENISCAL POSTERIOR ROOT TEARS IN THE ADOLESCENT KNEE: IS THE DIAGNOSIS MISSED, MENTIONED, OR MADE?

Background:The meniscal roots play a vital role in maintaining proper knee kinematics. Neglected meniscal root tears place excess stress on the articular cartilage and increase the risk of premature osteoarthritis. As opposed to medial meniscal root tears, lateral meniscal posterior root tears (LMPRTs) are more likely to be associated with anterior cruciate ligament (ACL) pathology. Failure to identify and address meniscal root tears may place undue loads on ACL grafts and lead to inferior post-surgical outcomes.Purpose:To examine preoperative knee magnetic resonance imaging (MRI) radiologist interpretations for the identification of lateral meniscal root pathology in children and adolescents.Methods:We performed a retrospective review of children and adolescents that underwnent knee arthroscopy between 3/1/2010 and 4/1/2020 and had an arthroscopically confirmed LMPRT. Arthroscopic findings were compared to the reading radiologist’s preoperative MRI interpretations. LMPRTs were graded using the LaPrade classification. ANOVA was performed to assess if body mass index (BMI), open physes, time from injury to MRI, time from MRI to surgery, MRI magnet field strength, musculoskeletal radiologist designation, insurance type and tear grade were associated with the preoperative MRI identification of a LMPRT.Results:During the study period, 1285 knee arthroscopies were performed. 607 of which were ACL reconstructions. 54 children were found to have a LMPRT arthroscopically and all were associated with an ACL tear 54/607 (9%). One patient had 2 preoperative MRIs for a total of 55 MRIs in 54 pateints. Average age was 16 years (range 14-21). Preoperative MRI diagnosis of a LMPRT was made in only 14/55 (25%) and missed in 22/55 (40%). In 19/55 (35%), pathology of the lateral meniscus nonspecific to the root was mentioned. Lateral joint line tenderness was present in 23/54 (46%). There was no statistical significance found in regards to patient BMI, skeletal maturity, time from injury to MRI, time from MRI to surgery, MRI magnet strength, if the radiologist was musculoskeletal fellowship-trained, or insurance type, with a reliable diagnosis. (Table)Conclusion:The final interpretation of preoperative MRIs did not provide a clear definitive diagnosis of a LMPRT in 75 % in patients. As the intraoperative management of LMPRTs can be involved and diverge from standard meniscal work, preoperative diagnosis would be advantageous. All LMPRTs in this study were associated with a concomitant ACL tear. Surgeons caring for ACL tears in children and adolescents should be prepared to treat a LMPRT regardless of a inconclusive MRI interpretation for meniscal root pathology.

Posterior Root Repair of Medial Meniscus Combined With Valgus Opening Wedge Tibial Osteotomy

The medial meniscal root tear, a particular meniscal injury at the level of its posterior bone insertion, leads to a loss of impact absorption and load distribution capacity, similar to total meniscectomy. Therefore, its repair is fundamental for knee joint longevity. This type of injury often occurs in middle-aged patients with lower limbs varus malalignment, which results in mechanical overloading of the medial compartment and induces premature cartilage wear out. The success of meniscal root repair, with meniscal bone reinsertion, depends on the correction and realignment of varus deformities greater than 5° for physiological levels. In this situation, corrective tibial osteotomy combined with meniscal repair is indicated. Our goal is to describe the step-by-step technique of the valgus opening wedge tibial osteotomy combined with the arthroscopic reinsertion of the posterior meniscal root in tibia during the treatment of a patient with varus deformity and medial meniscus root tear.

Midterm Outcomes of Posterior Medial Meniscus Root Tear Repair: A Systematic Review

Background: Whereas there has been growing interest in surgical repair of posterior medial meniscus root tears (PMMRTs), our understanding of the medium- and long-term results of this procedure is still evolving. Purpose: To report midterm clinical outcomes from PMMRT repairs. Study Design: Systematic review. Methods: A literature review for this systematic analysis was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We identified studies that reported the results of arthroscopic repair of PMMRTs. Functional and imaging outcomes were reviewed and summarized. Results: In total, 28 studies with a total of 994 patients (83% female) with an overall mean age of 57.1 were included in this review. Clinical outcomes (Lysholm, International Knee Documentation Committee, Hospital for Special Surgery, and Tegner scores) were improved at final follow-up in all studies. Of patients, 49% had radiographic progression of at least 1 grade in the Kellgren-Lawrence scale at a mean follow-up of 4.0 years in 11 studies. Cartilage degeneration had progressed at least 1 grade on magnetic resonance imaging scans in 23% of patients at a mean follow-up of 31.6 months in 4 studies. Conclusion: PMMRT repairs provide a functional benefit with consistent improvements in clinical outcome scores. There is some evidence that PMMRT repair slows the progression of osteoarthritis but does not prevent it at midterm follow-up.

Mild to Moderate Varus Alignment in Relation to Surgical Repair of a Medial Meniscus Root Tear: A Matched-Cohort Controlled Study With 2 Years of Follow-up

Background: Increased varus alignment of the lower extremity is known to be a poor prognostic factor for the surgical repair for a medial meniscus root tear (MMRT). However, given the concept of constitutional varus, which is present in a substantial portion of the normal population, the generally accepted surgical indication for MMRT concerning a varus alignment of 5° may be unnecessarily narrow. Purpose: To compare the surgical outcomes of arthroscopic transtibial pullout repair of MMRT according to the degree of varus alignment of the lower extremity. Study Design: Cohort study; Level of evidence, 3 Methods: Patients who underwent isolated arthroscopic transtibial pullout repair of MMRT between January 2010 and July 2017 at one institution and had a minimum follow-up of 2 years were included in this study. Patients were classified into 1 of 2 groups: the experimental group (n = 22) included patients with a preoperative hip-knee-ankle angle between 5° and 10° varus (mild to moderate varus alignment) and the control group (n = 51) included those with a preoperative hip-knee-ankle angle <5° varus (neutral alignment). Clinical scores and radiographic parameters were compared between the groups to assess surgical outcomes, which were statistically matched for potential confounders (age, body mass index, the severity of cartilage lesion) by use of the inverse probability of treatment weighting. A noninferiority trial was performed comparing the experimental and control groups in terms of subjective outcomes (International Knee Documentation Committee subjective and Lysholm scores) and objective outcomes (postoperative medial meniscal extrusion and the rate of osteoarthritis progression). Results: There were no statistically significant differences in surgical outcomes between the groups in subjective and objective aspects, which were consistent before and after inverse probability of treatment weighting. Apart from the clinical improvement observed in both groups, overall degenerative changes in the knee were found, although progression rates did not differ between the groups. In terms of the noninferiority trial, the overall surgical outcomes in the experimental group were not inferior to those in the control group. Conclusion: The short-term surgical outcomes of arthroscopic transtibial pullout repair for MMRT of patients with mild to moderate varus alignment were not inferior to but rather comparable with those with neutral alignment in terms of subjective and objective aspects. Therefore, it would be inappropriate to exclude patients with a diagnosis of MMRT from being indicated for the surgery simply because of mild to moderate varus alignment.

Increased posterior tibial slope results in increased incidence of posterior lateral meniscal root tears in ACL reconstruction patients.

While the association with acute anterior cruciate ligament (ACL) tears has been established, other risk factors and associated pathologies which occur with a concomitant lateral meniscal posterior root tear (LMPRT) are not well defined. The purpose of this study was to compare the risk factors and concomitant pathologies between patients with LMPRT and patients without LMPRTs in the setting of a primary ACL tear. Patients with a LMPRT identified at the time of primary ACL reconstruction by a single surgeon were identified. These patients were matched by age and sex to patients undergoing primary ACL reconstruction who were not found to have lateral meniscus root tears (control group) in a 1:1 ratio. Lateral posterior tibial slope (PTS), medial PTS, lateral femoral condyle height and depth, lateral tibial plateau depth, and lateral tibial plateau subluxation were measured on MRI. Anteroposterior full-limb alignment radiographs were used to measure the medial proximal tibia angle (MPTA), the mechanical lateral distal femoral angle (mLDFA), and the mechanical weightbearing axis for the injured extremity. One-hundred three patients were included in both the LMPRT group and the matched control group. Patients with a LMPRT had a significantly steeper lateral PTS (9.1° vs. 7.0°, p = 0.001), a steeper medial PTS (7.0° vs. 6.0°, p = 0.03), and a greater lateral-to-medial slope asymmetry (2.0° vs. 1.0°, p = 0.001). There were no differences in lateral femoral condyle depth or height, lateral tibial plateau depth, lateral tibial plateau subluxation, MPTA, mLDFA, or mechanical weightbearing axis between groups. There was a significantly increased incidence of medial meniscus ramp lesions in patients with lateral meniscus posterior root tears compared with controls (34.0% vs. 15.5%, odds ratio: 2.8, p = 0.002). There were no associations with concomitant ligament injuries, medial meniscus root tears, or non-ramp tears based on case/control grouping. In conclusion, LMPRTs in the setting of primary ACL injuries were associated with significantly increased lateral and medial PTSs, and increased asymmetry between lateral and medial PTSs. In addition, clinicians should be aware of the increased incidence of concurrent medial meniscal ramp lesions in patients with LMPRTs. Knowledge of these associations helps guide clinical decision-making and counselling of patients in the setting of ACL tears with concomitant LMPRTs. IV.

Medial vs. Lateral Meniscus Root Tears: Differences in Presentation, Treatment and Surgical Outcomes

To compare medial (MMRT) versus lateral meniscus posterior horn root tear (LMRT) injury presentation, treatment, clinical outcomes following root repair, and risk factors for failure. One hundred and forty-one root tears in 137 patients were included. Radiographs were graded using Kellgren-Lawrence scores. MRI’s were reviewed for root tear classification and meniscus extrusion. Sub-analysis was performed on 62 patients who underwent root repair. Tegner, Lysholm, IKDC scores and progression to arthroplasty were analyzed in the repair groups. Patient demographics, radiographic findings, and clinical outcomes were compared between MMRT and LMRT. Of the 141 root tears, 109 were MMRTs, 30 were LMRTs, and two patients had both. At the time of injury, patients with MMRTs had a significantly higher age (MMRT=51.4 vs LMRT=24.6, p<.0001), BMI (MMRT=32.1 vs LMRT 25.8, P < .0001), KL score, (MMRT=1.3 vs LMRT=0.6, p<.0001), and higher rate of major meniscal extrusion (MMRT= 72% vs LMRT=20%, p<.0001). Of the 30 LMRT, 30/30 (100.0%) were treated with meniscal repair. With MMRT, 52/109 (48%) were treated non-operatively, 27/109 (25%) were treated with partial meniscectomy, and 30/109 (27%) were treated with meniscal repair. Sixty-two patients underwent meniscus root repair (30 medial, 30 lateral and 2 combined medial and lateral repairs) with an average 41 month follow-up. LMRT had significantly increased IKDC (LMRT=89.5, MMRT=80.4, p=0.02) and Tegner scores (LMRT=6.5, MMRT=5.1, p<0.05) compared to MMRT. LMRT repairs also had increased Lysholm scores, but the difference was not significant (LMRT=93.9, MMRT=89.6, p=0.20). Compared to MMRTs, LMRTs occur in younger male patients with lower BMI, less cartilage degeneration, less extrusion on MRI, and more commonly with a ligament injury. While good to excellent clinical outcomes were attained in select patients for both medial and lateral meniscus root repair, LMRTs had overall better results after repair, likely due to differences in injury characteristics.

Clinical and Radiological Outcomes of Meniscal Repair Versus Partial Meniscectomy for Medial Meniscus Root Tears: A Systematic Review and Meta-analysis.

Background:Given the superiority of meniscal repair over partial meniscectomy according to biomechanical data, the clinical outcomes of meniscal repair are likely to be better than those of partial meniscectomy for a medial meniscus root tear (MMRT).Purpose/Hypothesis:This review was designed to compare the clinical and radiological results between meniscal repair and partial meniscectomy for MMRTs. It was hypothesized that meniscal repair would result in better clinical and radiological results compared with partial meniscectomy.Study Design:Systematic review; Level of evidence, 4.Methods:Studies were included in the review if they (1) included patients with MMRTs who underwent primary arthroscopic meniscal repair or partial meniscectomy and (2) analyzed validated patient-reported outcomes and/or radiological evaluations. Summary odds ratios (ORs) with 95% CIs were calculated to compare partial meniscectomy with meniscal repair for each outcome.Results:A total of 13 studies were included. The mean duration of follow-up was 33.5 and 47.2 months in the meniscal repair group and partial meniscectomy group, respectively. The change in the Lysholm score from preoperatively to postoperatively was statistically significantly in favor of meniscal repair (OR, 2.20 [95% CI, 1.55-3.12]), while no difference was found with respect to the change in the Tegner score between the 2 surgical approaches (OR, 1.21 [95% CI, 0.65-2.24]). The prevalence of postoperative severe knee osteoarthritis (OR, 0.31 [95% CI, 0.17-0.54]) as well as that of reoperations (OR, 0.05 [95% CI, 0.01-0.19]) were significantly in favor of meniscal repair.ConclusionBetter outcomes were seen after meniscal repair compared with partial meniscectomy for MMRTs, with greater improvements in Lysholm scores, and lower rates of progression to knee osteoarthritis, and lower reoperation rate.

Investigating the Chronology of Meniscus Root Tears: Do Medial Meniscus Posterior Root Tears Cause Extrusion or the Other Way Around?

Background:Meniscus root tears are increasingly being recognized. Meniscal extrusion has previously been associated with medial root tears; however, the relationship between secondary meniscal restraints, such as the meniscotibial (MT) ligament, extrusion, and root tears has yet to be formally evaluated.Purpose:To better understand the association between MT ligament competence, medial meniscal extrusion, and medial meniscus posterior root tears (MMPRTs) as well as to determine the progression of meniscal extrusion over time.Study Design:Case series; Level of evidence, 4.Methods:Serial magnetic resonance imaging (MRI) scans were reviewed for patients who showed evidence of medial meniscal extrusion and MMPRTs on at least 1 of ≥2 available MRI scans. All patients were symptomatic at the time of diagnosis. All MRI scans were analyzed independently by 2 board-certified musculoskeletal radiologists. MT ligament disruption, medial meniscal extrusion, and MMPRTs were recorded for each MRI scan. The time between MRI scans, presence of insufficiency fractures, and Outerbridge classification for the medial femur and tibia were also evaluated.Results:Overall, 27 knees in 26 patients were included in this study, with a total of 63 MRI scans analyzed (21 knees with 2 MRI scans, 3 with 3 MRI scans, and 3 with 4 MRI scans). All patients demonstrated clear medial meniscal extrusion and MT ligament disruption before the subsequent development of MMPRTs (P < .001). Mean extrusion at the time of initial MRI was 3.3 ± 1.1 mm and increased significantly to 5.5 ± 1.8 mm at the time of first imaging with an identified MMPRT (P < .001). The mean time between initial MRI and the first identification of an MMPRT on later MRI was 1.7 ± 1.6 years.Conclusion:In a sample of 27 symptomatic knees with serial MRI scans both before and after an MMPRT diagnosis, all patients demonstrated MT ligament disruption and associated meniscal extrusion before the development of subsequent medial meniscus root tears. These findings suggest that MT ligament disruption and medial meniscal extrusion represent early and predisposing events contributing to MMPRTs. Therefore, this provides a possible explanation of why meniscal extrusion is not corrected with medial meniscus root repair.

All-inside Techniques for Meniscal Radial Root Tear Repair

Meniscal radial root tears can disrupt the load-bearing function of the meniscus and worsen instability in anterior cruciate ligament–deficient knees. Paracentral radial tears adjacent to the root (types 1, 2, and 4) repaired with a transtibial pullout suture technique can lead to over-medialization of the meniscal root and a high-tension nonanatomic repair. We propose 2 all-inside techniques for anatomic repair of medial and lateral meniscal radial root tears with (1) an all-inside meniscal repair device and (2) an antegrade suture passer. We present the technical requirements and tips for these techniques. For lateral meniscal radial root repair with an all-inside meniscal repair device, ideal viewing is from an anterolateral portal with device entry from an anteromedial portal to reduce the risk of vascular injury. We recommend at least 2 stitches across the tear, with the depth setting limited to 18 to 20 mm for a central stitch and 16 mm or less for a peripherally placed stitch. For root repair with an antegrade suture passer, viewing should be from an anteromedial portal with the passer entering from an anterolateral portal. At least 2 stitches should be placed across the tear, with 1 central and 1 peripheral or 1 superior and 1 inferior.

Peripheral Stabilization Suture to Address Meniscal Extrusion in a Revision Meniscal Root Repair: Surgical Technique and Rehabilitation Protocol

Meniscal root tears are an increasingly recognized condition. These tears can cause the meniscus to become extruded outside the joint, which can diminish the biomechanical functionality of the meniscus. Anatomic repair of the meniscal root has previously been described, but this surgical procedure may not adequately address severe extrusion of the meniscal tissue. Additionally, when a primary anatomic repair fails, meniscal extrusion can increase, which can possibly accelerate joint degeneration if untreated. Therefore, the purpose of this Technical Note is to describe our surgical technique for revision medial meniscal root repair with a peripheral stabilization suture to address medial meniscal root tears with severe meniscal extrusion.

Remodified Mason-Allen suture technique concomitant with high tibial osteotomy for medial meniscus posterior root tears improved the healing of the repaired root and suppressed osteoarthritis progression.

To evaluate the results of the remodified Mason-Allen suture technique concomitant with high tibial osteotomy (HTO) for medial meniscal posterior root tears (MMPRTs). The hypothesis was that this procedure would improve clinical results, prevent progression of knee osteoarthritis and increase the healing rate of the repaired root. Total 17 patients of mean 51.5 ± 4.4years who were underwent this combined procedure for MMPRT completed this study. Lysholm and Hospital for Special Surgery (HSS) scores, Kellgren-Lawrence (KL) grade reflecting osteoarthritis progression were evaluated preoperatively and at the last follow-up. Medial meniscus extrusion (MME) was measured on magnetic resonance imaging preoperatively and at mean 26.1 ± 2.3months postoperatively. Second-look arthroscopy was performed at mean 25.1 ± 5.3months postoperatively. The healing status of the repaired root was classified as complete, partial and failed healing. The Outerbridge (OB) grade of the medial femoral condyle (MFC) was compared between index surgery and second-look arthroscopy. Mean follow-up duration was 66.4 ± 6.5months. Mean Lysholm and HSS mean scores improved significantly from preoperatively to the last follow-up: Lysholm: 56.9 ± 5.4 to 83.5 ± 6.0 (P < 0.001); HSS: 56.1 ± 6.0 to 81.7 ± 7.7 (P < 0.001). The mean mechanical alignment of the lower extremity was corrected from varus to the neutral range at the last follow-up. The preoperative KL grade was not significantly different from the KL grade at the last follow-up (P = 0.071). On MRI, mean MME increased from 3.0 ± 0.7mm to 3.1 ± 0.7mm (P = 0.046). Second-look arthroscopy showed 64.7% complete, 29.4% partial and 5.9% failed healing of the repaired root. The initial OB grade of the MFC showed no progression (P = 0.103). The remodified Mason-Allen suture technique concomitant with HTO for MMPRTs significantly improved clinical outcomes and suppressed OA progression at 66.4months. However, this procedure produced limited complete healing of the repaired roots in 64.7% of patients. IV.