Medial Meniscal Root Tears Research Articles

L’arthrose du compartiment fémoral tibial médial précède la lésion de la racine méniscale médiale exprimée par un épisode douloureux soudain

BackgroundAn event of painful popping is a highly predictive clinical sign of medial meniscal posterior root tears (MMPRTs) in middle-aged to older patients. There are lack of studies about the prevalence of a painful popping event and the condition of the medial compartment at the time of popping event in MMPRTs. HypothesisWe hypothesized that most of MMPRTs with a single painful popping event would show pre-existed pathologic medial meniscal extrusion (MME) and articular cartilage degeneration, and larger contact area of medial femoral condyle to medial tibial plateau could affect the MME. In addition, MME would be correlated with knee osteoarthritis. Patients and MethodsThirty-eight patients (mean age 58.5±10.5) who had painful popping within 3 weeks were included. On MRIs, absolute MME, relative percentage of extrusion (RPE), MME-medial femoral condyle (MFC)/medial tibial condyle (MTC) at 0̊ ratio, and medial compartments’ Modified Outerbridge Scale (MOS) were evaluated. Kellgren-Lawrence (K-L) grade was also assessed. ResultsThe MME parameters including absolute MME, RPE, and the ratio between MME and MFC/MTC at 0̊ were 2.9±1.2mm, 22.0±10.3%, and 3.2±1.3. Patients with MOS and K-L grade≥2 were 33 (86.8%) and 32 (84.2%). Patients were divided into MME ≥3mm (group G, n=20) and MME<3mm (group L, n=18). The MME parameters were significantly greater in group G than group L (all, p<0.001). The group G had worse osteoarthritis progression in terms of MOS and K-L grade than the group L (p=0.035 and 0.077, respectively) MME≥3mm showed significantly association with MOS≥3 (p=0.045). DiscussionMore than 80% of MMPRT patients with an event of painful popping within 3 weeks showed that medial compartment degeneration preceded the event of popping. Therefore, identification of MME and articular cartilage degeneration at the time of painful popping in MMPRTs could be helpful when the surgeon determines the most appropriate treatment. Level of EvidenceIV, Case-series.

Evaluation of Healing After Medial Meniscal Root Repair Using Second-Look Arthroscopy, Clinical, and Radiological Criteria

Background: Previous studies have reported various healing rates (0%-100%) as evaluated by second-look arthroscopy after repair of medial meniscal root tears (MMRTs). Such variable results might provoke suspicion of the necessity for repair. Furthermore, the effect of meniscal healing on the clinical outcomes has not been reported. Purpose: To more precisely determine the healing rate of MMRTs repaired through the transseptal portal, which could provide objective visualization of the healed meniscus, and to identify the effect of meniscal healing on the clinical and radiological outcomes. Study Design: Case series; Level of evidence, 4. Methods: Between June 2010 and April 2015, 56 patients underwent pullout suture for MMRT. Lysholm score, Hospital for Special Surgery score, International Knee Documentation Committee subjective score, medial joint space height, and Kellgren-Lawrence (K-L) grade were evaluated. Thirty-three patients underwent second-look arthroscopy and were divided into a “stable healed group” and “unhealed group” according to their healing status, as evaluated through the transseptal portal. The intraoperative, clinical, and radiological outcomes of the 2 groups were compared. Results: All other clinical outcomes improved. However, medial joint space became significantly narrower (P < .001), and 23 patients (41%) showed K-L grade progression. On the basis of second-look arthroscopy, 23 patients (69.7%) were classified into a stable healed group and 10 (30.3%) into a unhealed group. The stable healed group showed a higher Hospital for Special Surgery score (P = .023), International Knee Documentation Committee subjective score (P = .031), and successful microfracture rate (P = .023), with less progression of medial joint space narrowing (P < .001) and K-L grade (P < .001). Conclusion: Despite degenerative change progression, clinical outcomes were improved. The successful healing rate was 69.7% after repair of MMRTs. Compared with the unhealed group, the stable healed group showed better clinical outcomes and less degenerative change progression.

Medial knee osteoarthritis precedes medial meniscal posterior root tear with an event of painful popping

BackgroundAn event of painful popping is a highly predictive clinical sign of medial meniscal posterior root tears (MMPRTs) in middle-aged to older patients. There are lacks of studies about the prevalence of a painful popping event and the condition of the medial compartment at the time of popping event in MMPRTs. HypothesisWe hypothesized that most of MMPRTs with a single painful popping event would show pre-existed pathologic medial meniscal extrusion (MME) and articular cartilage degeneration, and larger contact area of medial femoral condyle to medial tibial plateau could affect the MME. In addition, MME would be correlated with knee osteoarthritis. Patients and methodsThirty-eight patients (mean age 58.5±10.5) who had painful popping within 3 weeks were included. On MRIs, absolute MME, relative percentage of extrusion (RPE), MME-medial femoral condyle (MFC)/medial tibial condyle (MTC) at 0° ratio, and medial compartments’ Modified Outerbridge Scale (MOS) were evaluated. Kellgren-Lawrence (K-L) grade was also assessed. ResultsThe MME parameters including absolute MME, RPE, and the ratio between MME and MFC/MTC at 0° were 2.9±1.2mm, 22.0±10.3%, and 3.2±1.3. Patients who with MOS and K-L grade≥2 were 33 (86.8%) and 32 (84.2%). Patients were divided into MME≥3mm (group G, n=20) and MME<3mm (groupL, n=18). The MME parameters were significantly greater in group G than group L (all, p<0.001). The group G had worse osteoarthritis progression in terms of MOS and K-L grade than the group L (p=0.035 and 0.077, respectively) MME≥3mm showed significantly association with MOS≥3 (p=0.045). DiscussionMore than 80% of MMPRT patients with an event of painful popping within 3 weeks showed that medial compartment degeneration preceded the event of popping. Therefore, identification of MME and articular cartilage degeneration at the time of painful popping in MMPRTs could be helpful when the surgeon determines the most appropriate treatment. Level of evidenceIV, Case-series.

Diagnostic value of MRI for posterior root tear of medial and lateral meniscus

To explore diagnostic value of MRI on posterior root tear of medial and lateral meniscus. From January 2012 to January 2016, clinical data of 43 patients with meniscal posterior root tear confirmed by arthroscopy were retrospective analyzed, including 25 males and 18 females, aged from 27 to 69 years old with an average age of(42.5±8.3)years old;27 cases on the right side and 16 cases on the left side. MRI examinations of 43 patients with tear of posterior meniscus root confirmed by knee arthroscopies were retrospectively reviewed. MRI images were double-blinded, independently, retrospectively scored by two imaging physicians. Sensitivity, specificity and accuracy of MRI diagnosis of lateral and medial meniscus posterior root tear were calculated, and knee ligament injury and meniscal dislocation were calculated. Forty-three of 143 patients were diagnosed with meniscus posterior root tears by arthroscopy, including 19 patients with lateral tears and 24 patients with medial tears. The sensitivity, specificity and accuracy in diagnosis of posterior medial meniscus root tears for doctor A were 91.67%, 86.6% and 83.9% respectively, and for doctor B were 87.5%, 87.4% and 87.4%, 19 patients with medial meniscal protrusion and 2 patients with anterior cruciate ligament tear. The sensitivity, specificity and accuracy in diagnosis of posterior lateral meniscus root tears for doctor A were 73.7%, 79.9% and 79% respectively, and for doctor B were 78.9%, 82.3% and 82.5%, 4 patients with lateral meniscus herniation and 16 patients with cruciate ligament tear. Kappa statistics for posterior medial meniscus root tears and posterior lateral meniscus root tears were 0.84 and 0.72. MRI could effectively demonstrate imaging features of medial and lateral meniscal root tear and its accompanying signs. It could provide the basis for preoperative diagnosis of clinicians, and be worthy to be popularized.

Meniscus Root Repair vs Meniscectomy or Nonoperative Management to Prevent Knee Osteoarthritis After Medial Meniscus Root Tears: Clinical and Economic Effectiveness

Background: Medial meniscus root tears are a common knee injury and can lead to accelerated osteoarthritis, which might ultimately result in a total knee replacement. Purpose: To compare meniscus repair, meniscectomy, and nonoperative treatment approaches among middle-aged patients in terms of osteoarthritis development, total knee replacement rates (clinical effectiveness), and cost-effectiveness. Study Design: Meta-analysis and cost-effectiveness analysis. Methods: A systematic literature search was conducted. Progression to osteoarthritis was pooled and meta-analyzed. A Markov model projected strategy-specific costs and disutilities in a cohort of 55-year-old patients presenting with a meniscus root tear without osteoarthritis at baseline. Failure rates of repair and meniscectomy procedures and disutilities associated with osteoarthritis, total knee replacement, and revision total knee replacement were accounted for. Utilities, costs, and event rates were based on literature and public databases. Analyses considered a time frame between 5 years and lifetime and explored the effects of parameter uncertainty. Results: Over 10 years, meniscus repair, meniscectomy, and nonoperative treatment led to 53.0%, 99.3%, and 95.1% rates of osteoarthritis and 33.5%, 51.5%, and 45.5% rates of total knee replacement, respectively. Meta-analysis confirmed lower osteoarthritis and total knee replacement rates for meniscus repair versus meniscectomy and nonoperative treatment. Discounted 10-year costs were $22,590 for meniscus repair, as opposed to $31,528 and $25,006 for meniscectomy and nonoperative treatment, respectively; projected quality-adjusted life years were 6.892, 6.533, and 6.693, respectively, yielding meniscus repair to be an economically dominant strategy. Repair was either cost-effective or dominant when compared with meniscectomy and nonoperative treatment across a broad range of assumptions starting from 5 years after surgery. Conclusion: Repair of medial meniscus root tears, as compared with total meniscectomy and nonsurgical treatment, leads to less osteoarthritis and is a cost-saving intervention. While small confirmatory randomized clinical head-to-head trials are warranted, the presented evidence seems to point relatively clearly toward adopting meniscus repair as the preferred initial intervention for medial meniscus root tears.

Clinical and Radiological Results with Second-Look Arthroscopic Findings after Open Wedge High Tibial Osteotomy without Arthroscopic Procedures for Medial Meniscal Root Tears.

PurposeTo identify the structural integrity of the healing site after medial open wedge high tibial osteotomy (MOWHTO) in patients with a posterior root tear of the medial meniscus (PRTMM) and chondral lesion by second-look arthroscopy and to determine the clinical and radiological findings.Materials and MethodsFrom August 2010 to June 2016, 52 consecutive patients underwent MOWHTO and arthroscopic examination without a chondral resurfacing procedure and meniscal treatment for PRTMM. Twenty-four patients were available for second-look arthroscopic evaluation. The mean follow-up period was 19.5 months (range, 5 to 46 months). Clinical evaluation was based on the Lysholm knee scores and Hospital for Special Surgery (HSS) scores.ResultsThere were 5 lax healing, 6 scar tissue, 13 failed healing of PRTMM. Definite change of chondral lesion was not observed. The Kellgren-Lawrence grade did not improve according to the follow-up plain radiograph. The mean Lysholm score improved from 34.7 preoperatively to 77.1 at the last follow-up, and the mean HSS score significantly increased from 36.5 to 82.4.ConclusionsThis study revealed a low rate of healing potency of PRTMM and chondral lesion after MOWHTO without any attempt for meniscal treatment or chondral resurfacing. The cartilage and healing status of PRTMM was not associated with improved clinical outcomes and radiological findings.

Novel technique for repairing posterior medial meniscus root tears using porcine knees and biomechanical study.

Transtibial pullout suture (TPS) repair of posterior medial meniscus root (PMMR) tears was shown to achieve good clinical outcomes. The purpose of this study was to compare biomechanically, a novel technique designed to repair PMMR tears using tendon graft (TG) and conventional TPS repair. Twelve porcine tibiae (n = 6 each) TG group: flexor digitorum profundus tendon was passed through an incision in the root area, created 5 mm postero-medially along the edge of the attachment area. TPS group: a modified Mason-Allen suture was created using no. 2 FiberWire. The tendon grafts and sutures were threaded through the bone tunnel and then fixed to the anterolateral cortex of the tibia. The two groups underwent cyclic loading followed by a load-to-failure test. Displacements of the constructs after 100, 500, and 1000 loading cycles, and the maximum load, stiffness, and elongation at failure were recorded. The TG technique had significantly lower elongation and higher stiffness compared with the TPS. The maximum load of the TG group was significantly lower than that of the TPS group. Failure modes for all specimens were caused by the suture or graft cutting through the meniscus. Lesser elongation and higher stiffness of the constructs in TG technique over those in the standard TPS technique might be beneficial for postoperative biological healing between the meniscus and tibial plateau. However, a slower rehabilitation program might be necessary due to its relatively lower maximum failure load.

Medial Meniscal Root Repair Using Curved Guide and Soft Suture Anchor.

Medial meniscal root tears have been repaired using various methods. Arthroscopic all-inside repair using a suture anchor is one of the popular methods. However, insertion of the suture anchor into the proper position at the posterior root of the medial meniscus is technically difficult. Some methods have been reported to facilitate suture anchor insertion through a high posteromedial portal, a posterior trans-septal portal, or a medial quadriceptal portal. Nevertheless, many surgeons still have difficulty during anchor insertion. We introduce a technical tip for easy suture anchor insertion using a 25° curved guide and a soft suture anchor through a routine posteromedial portal.

The Role of Meniscal Tears in Spontaneous Osteonecrosis of the Knee: A Systematic Review of Suspected Etiology and a Call to Revisit Nomenclature

Background: The cause of spontaneous osteonecrosis of the knee (SONK) and postarthroscopic osteonecrosis of the knee is unknown, and the mechanisms involved have been poorly characterized. Hypothesis/Purpose: The purpose of this study was to perform a detailed systematic review of the literature to examine proposed etiological mechanisms for SONK in order to establish an improved understanding of the processes involved. We hypothesized that the etiology of SONK would be multifactorial. Study Design: Systematic review. Methods: A systematic review of the literature was performed by searching PubMed, Medline, Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials. Inclusion criteria were all original research articles presented in the English language that reported on the suspected etiology of SONK. Reviews, case reports with fewer than 3 patients, cost-effectiveness studies, technical reports, editorial articles, surveys, special topics, letters to the editor, personal correspondence, and studies that only proposed factors for the progression of SONK were excluded. Results: After a comprehensive review of 255 articles, 26 articles were included for final analysis. Twenty-one (80.7%) of 26 articles implicated the role of the meniscus in the development of SONK, in an association with either meniscal tears or its development after meniscectomy. The medial meniscus and posterior meniscal root tears were implicated more frequently. All 4 studies incorporating histological findings supported the insufficiency fracture hypothesis as a pathological basis of SONK. Conclusion: Physicians should be cognizant of the high prevalence of medial meniscus root tears in patients with SONK. Meniscectomy and meniscal tears, particularly of the medial meniscus posterior root, increase contact pressures and create an environment from which insufficiency fractures can emanate. We believe the term SONK is a misrepresentation of the etiology and pathogenesis of the condition and should be replaced with subchondral insufficiency fractures of the knee. Further elucidation of the etiology is required.

Knee upside down

We present a case of a 19-year-old woman with a forced hyperextension trauma of the knee causing a posteromedial fracture, a medial meniscus root tear and rupture of the posterior...

Both Posterior Root Lateral-Medial Meniscus Tears With Anterior Cruciate Ligament Rupture: The Step-by-Step Systematic Arthroscopic Repair Technique

The occurrence of posterior root tear of both the lateral and medial menisci, combined with anterior cruciate ligament rupture, is rare. Problems may be encountered such as the difficulty to access the medial meniscal root tear, the confusing circumstances about which structure to repair first, and the possibility of the tunnel for each repair to become taut inside the tibial bone. We present the arthroscopy technique step by step to overcome the difficulties in an efficient and time-preserving manner.

Survival analysis after pullout refixation for medial meniscus root tear: Minimum 5-year of follow-up

Survival analysis after pullout refixation for medial meniscus root tear: Minimum 5-year of follow-up

Repair of posterior medial meniscal root tears in the setting of Outerbridge III and IV cartilage damage

Objectives:Reporting the clinical outcomes of our cohort of patients who underwent arthroscopic transtibial posterior medial meniscal root tear repair (MMRTr) in those patients who had Outerbridge cartilage degeneration of III or IV.Methods:29 consecutive patients with isolated MMRT underwent trans-tibial repair with all patients completing pre-operative scoring and 20 patients completing both pre and post-operative questionnaires. Of this there were 18 patients who had Outerbridge III or IV cartilage degeneration in the medial compartment at the time of surgery. Data was collected prospectively to include the Oxford Knee Score (OKS), the Lysholm Score (LS), the Tegner Activity Level Scale (TS) and International Knee Documentation Committee Score (IKDC).Results:In the 18 patient cohort there was a mean age at the time of surgery of 57.22 (range 40 – 71) years and the mean follow up period was 26.77 (7.2 – 94.53) months. There was statistically significant improvement across all scoring measures (OKS p = 5.94e-07, LS p = 2.40e-07, IKDC p = 4.17e-06 and TS p = 0.023) in this cohort.Conclusion:There was a significant improvement in the clinical outcomes of all patients who underwent MMRTr despite the presence of Outerbridge III or IV cartilage injury.

Minimum 1 year results of pull-out suture repair with modified Mason-Allen stitch in medial meniscus root tear

Minimum 1 year results of pull-out suture repair with modified Mason-Allen stitch in medial meniscus root tear

Chondral lesions with medial meniscal posterior root tear are located more medially and more progressive than those with other meniscal tears

Chondral lesions with medial meniscal posterior root tear are located more medially and more progressive than those with other meniscal tears

Arthroscopic Repair of Posterior Meniscal Root Tears

Objectives:The purpose of this study was to compare subjective clinical outcomes in patients requiring arthroscopic transtibial pullout repair for posterior meniscus root tears of the medial and lateral menisci. We hypothesized that improvement in function and activity level would be similar among patients undergoing lateral and medial meniscal root repairs.Methods:This study was IRB approved. All patients who underwent posterior meniscal root repair by a single orthopaedic surgeon were included in this study. Detailed operative data were documented at surgery. Patients completed a subjective questionnaire, including Lysholm score, Tegner activity scale, WOMAC, SF-12 and patient satisfaction with outcome, which were collected preoperatively and at a minimum of two years postoperatively. Failure was defined as any patient who underwent revision meniscal root repair or partial meniscectomy following the index surgery.Results:There were 50 patients (16 females, 34 males) with a mean age of 37.8 years (range, 16.6-65.7) and a mean BMI of 27.3 (range, 20.5-49.2) included in this study. Fifteen patients underwent lateral meniscus root repair and 35 patients underwent medial meniscus root repair. Three patients who underwent lateral meniscus root repair required revision meniscus root repair surgery, while no patients who underwent medial meniscus root repair required revision surgery (p=0.26). There was a significant difference in preoperative and postoperative Lysholm score (53 vs. 78) (p<0.001), Tegner activity scale (2.0 vs. 4.0) (p=0.03), SF-12 physical component subscale (38 vs. 50) (p=0.001) and WOMAC (36 vs. 8) (p<0.001) for the total population. Median patient satisfaction with outcome was 9 (range, 1-10). There was no significant difference in mean age between lateral and medial root repair groups (32 vs. 40) (p=0.12) or gender (p=0.19). There was no significant difference in gender between lateral and medial root repair groups (p=0.95). There was a significant difference in concurrent ACL reconstructions between lateral versus medial root repair groups (67% vs. 17%) (p<0.001). There was no significant difference in average postoperative Lysholm score (75 vs. 80) (p=0.31), IKDC (72 vs. 71) (p=0.23), SF-12 physical component subscale (48.4 vs. 51.0) (p=0.85) or WOMAC score (2.7 vs. 1.7) (p=0.80) for lateral versus medial meniscus root repairs. There was no significant difference in median postoperative Tegner activity scale for lateral versus medial meniscus root repairs (4 vs. 4) (p=0.88) or in median patient satisfaction with outcome for lateral versus medial meniscus root repairs (9 vs. 9) (p=0.61).Conclusion:There were no differences in outcomes between patients who underwent medial versus lateral arthroscopic meniscus root repair surgery. All patients who underwent arthroscopic repair of medial or lateral meniscus root tears demonstrated a significant improvement in function and activity level at a minimum two year follow-up. Overall, patients were highly satisfied with their outcomes.

Patterns and Influencing Factors of Medial Meniscus Tears in Varus Knee Osteoarthritis.

PurposeTo investigate the patterns of medial meniscus (MM) tears in patients with varus knee osteoarthritis who underwent total knee arthroplasty and analyze the factors that could affect MM tears.Materials and MethodsThe patients (365 knees, 268 patients) were classified into three groups; group I with MM posterior horn (PH) tear only; group II with MM root tear only; and group III with MMPH plus root tear. The following factors were evaluated: age, gender, body mass index, varus deviation of the mechanical axis, medial proximal tibial angle, posterior tibial slope (PTS), and anterior cruciate ligament (ACL) integrity (normal, degeneration, and tear or absence).ResultsMM tears were identified in all knees. The patterns of the combined MMPH tears in group III were less complex than those in group I. Varus deviation and PTS were significantly greater in group III than groups I and II. In group III, there were significantly more cases of ACL tear or absence than groups I and II. The others showed no differences among three groups.ConclusionsSevere varus knee osteoarthritis was always accompanied by MM tears. Risk factors for MMPH plus root tears were severe varus deformity, great PTS, and ACL tear or absence.

Chondral lesions with medial meniscal posterior root tear are located more medially and more progressive than those with other meniscal tears

Chondral lesions with medial meniscal posterior root tear are located more medially and more progressive than those with other meniscal tears

Comparison of Medial and Lateral Meniscus Root Tears.

The meniscus root plays an essential role in maintaining the circumferential hoop tension and preventing meniscal displacement. Studies on meniscus root tears have investigated the relationship of osteoarthritis and an anterior cruciate ligament tear. However, few studies have directly compared the medial and lateral root tears. To assess the prevalence of meniscal extrusion and its relationship with clinical features in medial and lateral meniscus root tears, we performed a retrospective review of the magnetic resonance imaging (MRI) results of 42 knee patients who had meniscus posterior horn root tears and who had undergone arthroscopic operations. The presence of meniscal extrusion was evaluated and the exact extent was measured from the tibial margin. The results were correlated with arthroscopic findings. Clinical features including patients’ ages, joint abnormalities, and previous trauma histories were evaluated. Twenty-two patients had medial meniscus root tears (MMRTs) and twenty patients had lateral meniscus root tears (LMRTs). Meniscal extrusion was present in 18 MMRT patients and one LMRT patient. The mean extent of extrusion was 4.2mm (range, 0.6 to 7.8) in the MMRT group and 0.9mm (range, -1.9 to 3.4) in the LMRT group. Five patients with MMRT had a history of trauma, while 19 patients with LMRT had a history of trauma. Three patients with MMRT had anterior cruciate ligament (ACL) tears, while 19 patients with LMRT had ACL tears. The mean age of the patients was 52 years (range: 29–71 years) and 30 years (range: 14–62 years) in the MMRT and LMRT group, respectively. There was a significant correlation between a MMRT and meniscal extrusion (p<0.0001), and between an ACL tear and LMRT (p<0.0001). A history of trauma was significantly common in LMRT (p<0.0001). LMRT patients were significantly younger than MMRT patients (p<0.0001). Kellgren-Lawrence (K-L) grade differed significantly between MMRT and LMRT group (p<0.0001). Meniscal extrusion is common in patients with MMRTs. However, it is rare in patients with LMRTs, which are more commonly associated with a history of trauma and ACL tears.

A new arthroscopic classification of degenerative medial meniscus root tear that correlates with meniscus extrusion on magnetic resonance imaging

BackgroundTo determine a new classification system for medial meniscus root tears (MMRT) based on arthroscopic findings. Methods24 knees (55%) belonged to the nondisplaced or overlapped group, and 20 knees (45%) to the widely displaced group. Absolute meniscal extrusion was defined as distance between outer edge of the articular cartilage of tibial plateau and meniscal outer edge. Relative extrusion was defined as extruded meniscus width divided by entire meniscal width, multiplied by 100. The proportion of knees with major (>3mm) extrusion were compared in two groups, as were the severity of chondral wear and osteoarthritic change. ResultsAbsolute (4.6mm vs. 3.7mm, P=0.006) and relative (46% vs. 39%, P=0.042) extrusion of the medial meniscus were greater in widely displaced than in nondisplaced or overlapped group. Medial joint space width was significantly narrower in the widely displaced than in the nondisplaced or overlapped group (3.0mm vs. 4.0mm, P=0.007). The widely displaced group had a 4° greater varus deformity, and higher rates of major extrusion (>3mm), grade III or IV chondral wear in the medial femoral condyle (60% vs. 29%, P=0.039) and medial compartment osteoarthritis (75% vs. 21%, P=0.001) than did the nondisplaced or overlapped group. ConclusionsWidely displaced MMRT had greater meniscal extrusion and more severe chondral wear and osteoarthritis than did nondisplaced or overlapped MMRT. In this novel classification system, the stage of MMRT severity was associated with tear site displacement. Level of evidenceCase series (level IV).