Medial Meniscus Posterior Root Research Articles

Medial meniscus posterior root tears with advanced osteoarthritis or subchondral insufficiency fracture are good indications for unicompartmental knee arthroplasty at a minimum 2-year follow-up

IntroductionThe outcomes of unicompartmental knee arthroplasty (UKA) in the presence and absence of medial meniscus posterior root tears (MMPRTs) have not been compared. This study compared the characteristics and clinical outcomes of patients undergoing UKA with and without MMPRTs.Materials and methodsThis study analyzed 68 patients. The presence or absence of MMPRTs was evaluated using preoperative magnetic resonance imaging. Patient characteristics, clinical scores before surgery and at the final evaluation, and imaging findings were compared between patients with and without MMPRTs. Multiple regression analysis was conducted on postoperative visual analog scale (VAS)-pain scores.ResultsMMPRTs were present in 64.7% (44/68) of patients. Patients with MMPRTs were significantly younger (67.8 ± 8.2 vs. 75.0 ± 7.1 years, p < 0.001) and had a shorter duration from the development of symptoms to the time of surgery than those without (6.8 ± 8.4 vs. 36.1 ± 38.9 months, p < 0.001). Component placement or lower-limb alignment did not significantly differ between the groups. Preoperative clinical scores were not significantly different between the groups; however, patients with MMPRTs showed significantly better postoperative VAS-pain scores than those without (10.0 ± 9.0 vs. 28.2 ± 26.0 points, p = 0.026). Multiple regression analysis of postoperative VAS-pain scores revealed the significant effect of duration from the development of symptoms to the time of surgery (p = 0.038).ConclusionsPatients undergoing UKA with MMPRTs were younger with less radiographic osteoarthritic changes compared to those without MMPRTs, and their postoperative VAS-pain scores were significantly superior. The duration from the development of symptoms to the time of surgery significantly influenced postoperative pain in patients undergoing UKA.

Comparison of the effects between arthroscopic transtibial pullout technique and all-inside repair in the treatment of medial meniscus posterior root tears

Comparison of the effects between arthroscopic transtibial pullout technique and all-inside repair in the treatment of medial meniscus posterior root tears

Association Between Insufficient Restoration of Meniscal Tension During Surgical Repair of Medial Meniscus Root Tear and Surgical Outcomes: Clinical Implication of Curtain-Cliff Sign.

Despite the clinical benefits over nonoperative treatment or meniscectomy, the clinical outcomes of surgical repair for medial meniscus posterior root tear (MMRT) remain suboptimal, which may be attributed to the insufficient restoration of meniscal hoop tension during surgery. To analyze the clinical outcomes of surgical repair of MMRT based on the appearance of the meniscal tension observed immediately after surgery. Cohort study; Level of evidence, 3. Electronic medical records of patients who underwent arthroscopic transtibial pull-out repair of MMRT between 2010 and 2021 were retrospectively reviewed. Patients with at least a 2-year follow-up and whose overall meniscal status after the surgical repair could be evaluated via arthroscopic images or videos were eligible to be included. Patients were classified based on the presence of the curtain-cliff sign, potentially implying insufficient postoperative meniscal hoop tension (group 1, patients without the curtain-cliff sign; group 2, patients with the curtain-cliff sign). Regression analysis was performed to evaluate whether the curtain-cliff sign reflects postoperative meniscal extrusion. Subsequently, comparative analyses were conducted between the 2 groups regarding baseline demographic data, clinical scores, intraoperative data, and radiologic parameters. A total of 79 patients were included (group 1, 59 patients; group 2, 20 patients). Regression analysis revealed a significant association between the curtain-cliff sign and postoperative meniscal extrusion, suggesting its potential to reflect the postoperative meniscal tension. In the between-group comparisons, there were no differences in baseline demographic data, preoperative clinical scores, and preoperative radiologic variables. However, at the final follow-up, group 2 showed a significantly lower International Knee Documentation Committee subjective score compared with group 1 (group 1, 61.7 ± 14.4; group 2, 52.9 ± 12.5; P = .017), while no significant differences were found in the visual analog scale for pain score and Lysholm score. Additionally, group 2 exhibited significantly higher postoperative meniscal extrusion compared with group 1, which was measured at both the midpoint of the medial femoral condyle (group 1, 4.0 ± 1.1 mm; group 2, 5.1 ± 1.5 mm, P = .004) and the posterior border of the medial collateral ligament (group 1, 4.4 ± 1.2 mm; group 2, 5.7 ± 1.5 mm; P = .004), with more pronounced progression compared with the preoperative status at these sites. Consistently, the progression of both the osteoarthritis grade and the hip-knee-ankle angle compared with preoperatively was significantly greater in group 2. In patients in whom the restoration of meniscal tension appears insufficient immediately after surgical repair of MMRT, relatively poor clinical outcomes can be anticipated. The findings of this study suggest that efforts to reinforce meniscal tension may be required during surgical repair of MMRT in some cases, especially those showing the curtain-cliff sign.

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

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

Gait Kinetics in Medial Meniscus Posterior Root Tears: Investigating Protective Strategies and the Effects of Root Repair

Objectives To investigate changes in external moments in medial meniscus posterior root tear (MMPRT) patients, and the effect of medial meniscus posterior root repair (MMPRR) in restoring normal kinetics. Methods We present preliminary findings from six subjects with MMPRT, four with MMPRR, and three healthy age-matched control participants (CON). Participants walked on level ground at a self-selected gait speed. Data were collected using high-speed cameras and ground-embedded force plates. Peak knee moments for flexion-extension (KFM and KEM), abduction-adduction (KAbM, KAdM), and internal-external rotation (KERM, KIRM) were calculated using inverse dynamics during the stance phase of gait, and normalized to body mass and height. Group comparisons were conducted using the Kruskal-Wallis and Dunn test with Bonferroni correction. Results were considered statistically significant if p-values were less than 0.05. Results Both MMPRT and MMPRR groups exhibited significantly lower KFM relative to the CON group, suggesting a strategy to reduce quadriceps activation in both patient groups, which may persist after surgery. MMPRT patients showed significantly diminished KEM relative to both MMR and CON groups, indicating a strategy to reduce external knee forces following injury. MMPRR patients presented KEM that resembled the healthy control group, showing that repair surgery could potentially restore this gait variable. KAbM was statistically higher in the MMPRR and CON groups relative to MMPRT patients, which presented lower KAM than the other groups, suggesting a protective strategy to offload the medial compartment. KERM were significantly higher in the CON group compared to the MMT group, suggesting a protective strategy to avoid excessive external rotation by the MMT group. No significant differences were observed in KIRM across the three groups. Conclusion MMPRT leads to alterations in gait kinetics, compatible with a protective strategy to unload the knee and compensate for increased medial compartment contact pressures, which are partially restored following root repair.

Outcomes Following Isolated Medial Meniscus Posterior Root Repair Using An Anatomic Transtibial Pull-Out Technique In Patients Aged &gt; 60 Years: A Matched Cohort Study

Objectives To compare patient-reported outcomes following anatomic transtibial pull-out repair for isolated medial meniscus posterior root (MMPR) tears in patients &gt; 60 versus ≤60 years of age, as well as the incidence of repair failures. Methods Patients aged ≥18 years undergoing isolated anatomic transtibial pull-out repair for MMPR tears at a single institution between January 2016 and September 2020 were analyzed. Patients with minimum 2-year follow-up were divided based on age: &gt;60 versus ≤60 years. Patients completed IKDC, KOOS JR, and VR12 surveys before surgery and at final follow-up. Differences in outcome scores between age groups, as well as repair failures, defined by the need for repeat arthroscopy, were analyzed. Results Twenty patients aged ≥60 with a mean age of 65.7 ± 4.1 years (range, 60.2 – 74.9 years) were compared to 40 patients ≤ 60 years of age with a mean age of 49.3 ± 9.0 years (range, 23.4 – 59.8). Significant improvement in all outcomes scores was observed in both groups at final follow-up relative to pre-operative values. No significant difference in IKDC, KOOS JR, or VR12-Physical scores was observed between groups. Revision repair was required in one patient (2.5%) under age 60, but no patients over age 60. Conclusion Anatomic transtibial pull-out repair for MMPR tears resulted in improved outcome scores at minimum 2-year follow-up, with no significant differences among our cohorts of patients &gt;60 or ≤60 years of age. While chronologic age should be accounted for when discussing expectations and management of MMPR tears, a specific age cut-off should not exclude consideration for root repair, as appropriately selected patients &gt;60 years of age exhibit non-inferior outcomes compared to patients aged ≤60 years.

Complete medial meniscal root injury and medial collateral ligament injury are risk factors for increased medial meniscal extrusion

Objectives To evaluate the association between medial meniscus posterior root tear (MMRT) with anthropometric characteristics of the patient (age, weight, and height) and associated injuries identified on MRI (meniscal extrusion, medial collateral ligament [MCL] injury, bone edema, and subchondral fracture of the tibia). Methods The characteristics and associated injuries of 55 patients diagnosed with an injury (either partial or complete) of the root of the posterior horn of the medial meniscus, diagnosed on MRI and confirmed arthroscopically, were compared. Specifically, age, sex, anthropometric data, meniscal extrusion, associated MCL injury, and presence of associated bone edema were evaluated. Results There was a moderate positive correlation between the age of the patients and the degree of extrusion (r = 0.565; p &lt; 0.0001). Greater meniscal extrusion was observed in patients who had complete medial meniscus root tear (C-MMRT) (p = 0.008). Patients with MCL injury presented with significantly greater meniscal extrusion when compared to individuals without MCL injury (p = 0.042). Similarly, the incidence of bone bruising was higher in patients with a MMRT with an associated MCL injury, when compared to patients without concomitant MCL injury (p=0.012). Conclusion Patients with a C-MMRT had greater meniscal extrusion than patients with a partial medial meniscus root tear (P-MMRT). The presence of a concomitant MCL injury was significantly associated with the meniscal extrusion in patients with concomitant meniscal root injury. The presence of associated bony edema was not associated with meniscal extrusion, but was significantly more common in patients with C-MMRT when there was an associated MCL injury compared to those without an associated MCL injury.

Arthroscopic Suture Anchor Repair With Modified Mason-Allen Technique for Medial Meniscus Posterior Root Tear

Medial meniscal posterior root tears are a well-known risk factor for knee osteoarthritis. Transtibial pullout repair is mostly reported, and good results have been reported for pullout repair using the modified Mason-Allen technique; techniques using suture anchors have also been reported. Herein, we report a technique for suture anchor repair using the modified Mason-Allen technique. An anchor with 2 sutures is inserted at the attachment site of the medial meniscal root via the posteromedial portal using a curved guide. A vertical suture was made on the posterior portion of the meniscus with one suture, and another suture is then inserted just medial to the vertical suture and tied over the first vertical suture using a self-locking sliding knot through the anteromedial portal. This technique may potentially improve medial meniscal posterior root tears repair outcomes and provide some technical advantages, especially in combination with high tibial osteotomy.

Suture anchor and transtibial pullout refixation of the posterior medial meniscus root tears restore tibiofemoral contact pressure and area to intact meniscus levels.

To compare the load distributed to the medial tibial articular cartilage after refixation of posterior medial meniscus root tears between the suture anchor and transtibial pullout techniques in posterior medial meniscus root tears. Twelve Thiel's embalmed human cadaveric knees are used and divided into three groups (four knees in each group): (1) intact meniscus (IM), (2) fixation with suture anchor technique (SA) and (3) fixation with transtibial pullout technique (TP). Each group applies an axial compression load up to 1500 N by Instron E 10000 at two knee flexion angles (0° and 60°). A Tekscan 4000 pressure sensor is used to record the contact pressure and the contact area for each testing condition. The contact pressure and the contact area between the three conditions are not significantly different at 0° and 60° knee flexion angles. The peak contact pressure and contact area are 3734.8 ± 2642.2 kPa, 288.2 ± 115.0 mm2, 4510 ± 2930.5 kPa, 204.4 ± 36.8 mm2 and 5328.8 ± 2607.7 kPa, 219.2 ± 84.7 mm2 in IM, SA and TP, respectively. Both suture anchor and transtibial pullout refixation of PMMRT can restore contact pressure and contact area similar to the intact meniscus. This finding suggests that either technique can be reliably used in clinical practice to preserve joint function and potentially reduce the risk of osteoarthritis progression following posterior medial meniscus root tear repairs. Level III.

Arthroscopic Repair of Medial Meniscus Posterior Root Tear with Adjustable Titanium Plate Fixation.

Medial meniscus injury is one of the most prevalent knee disorders, with posterior root tears occurring in approximately 10% to 21% of affected individuals. A posterior root tear disrupts the meniscus's continuous annular structure, compromising its ability to absorb pressure and protect the knee's articular cartilage. If left untreated, this can result in increased stress on the cartilage, leading to conditions such as varus deformity and accelerated joint degeneration. Partial removal (resection) of the medial meniscus further exacerbates these issues, often leading to quicker joint deterioration. Repairing medial meniscus posterior root tears (MMPRTs) plays a crucial role in restoring the meniscus's structural integrity and improving knee biomechanics. Studies have shown that compared to partial medial meniscectomy or conservative treatments, repairing MMPRTs enhances clinical outcomes and significantly delays the onset of arthritis. This article details a surgical procedure that uses a single-suture, double-loop, adjustable titanium plate fixation technique under arthroscopy for effective MMPRT repair.

Quadriceps muscle strength of the affected limb in medial meniscus posterior root tears is negatively correlated with the progression of postoperative medial joint space narrowing

AbstractPurposeThe effect of quadriceps muscle strength on medial joint space (MJS) narrowing after repair for medial meniscus (MM) posterior root tears (MMPRTs) has not yet been determined. This study aimed to evaluate the effect of preoperative and postoperative quadriceps muscle strength on the change in MJS (ΔMJS) in MMPRTs.MethodsThirty patients who underwent pullout repair for MMPRTs were retrospectively evaluated. The MJS width using fixed‐flexion view radiographs, MM extrusion (MME) using magnetic resonance imaging, quadriceps muscle strength using the Locomo Scan‐II and clinical scores were measured and compared preoperatively and 1 year postoperatively. Correlations between the ΔMJS, change in MME (ΔMME), and preoperative and postoperative quadriceps muscle strength were evaluated using Spearman's rank correlation coefficient.ResultsMJS narrowing and MME progressed significantly at 1 year postoperatively (p &lt; 0.001). Quadriceps muscle strength in MMPRT knees and all clinical scores significantly improved at 1 year postoperatively (p &lt; 0.001). ΔMJS and ΔMME showed a significant positive correlation (0.50 ± 0.70 and 1.22 ± 0.92 mm, respectively; r = 0.516, p = 0.004). Both preoperative and postoperative quadriceps muscle strength in MMPRT knees showed significant negative correlations with ΔMJS (preoperative: r = −0.529, p = 0.003; postoperative: r = −0.477, p = 0.008) and ΔMME (preoperative: r = −0.431, p = 0.018; postoperative: r = −0.443, p = 0.014).ConclusionsIn pullout repair for MMPRTs, preoperative and postoperative quadriceps muscle strength in MMPRT knees was negatively correlated with the progression of MJS narrowing and MME. Rehabilitation with a focus on quadriceps muscle strengthening, including preoperative rehabilitation, may delay knee‐osteoarthritis progression after pullout repair for MMPRTs.Level of EvidenceLevel IV.

Biomechanical Comparison of Suture-Relay All-Suture Anchors and Conventional Suture Anchors for Posterior Medial Meniscus Root Repair in Porcine Models.

Posterior medial meniscus root (PMMR) tears (PMMRTs) can be repaired using various techniques to promote healing. However, the biomechanical properties of suture-relay all-suture anchor (ASA) versus conventional suture anchor (CSA) and loop-locking transtibial pullout (TTP) have not been well established. To compare the biomechanical properties of PMMR repairs using suture-relay ASA, CSA, and loop-locking TTP. Controlled laboratory study. A total of 33 fresh-frozen porcine knee joints with intact medial menisci were randomly divided into 3 groups, with 11 specimens in each group: ASA, CSA, and TTP. The study involved cyclic loading, with displacement measurements taken after 100, 500, and 1000 cycles. Subsequently, the specimens were loaded until clinical failure (defined as 3-mm displacement) and then to ultimate failure of the construct, with data recorded for displacement after cyclic loading, load to 3-mm displacement, and ultimate load to failure. After 1000 cyclic loadings, the suture-relay ASA group showed considerably less displacement than the loop-locking TTP group (1.8 ± 0.7 mm vs 2.9 ± 0.3 mm; P < .001), but the displacements did not differ considerably between the suture-relay ASA and CSA groups (2.2 ± 0.9 mm; P > .05). The mean loads to clinical failure were significantly greater in the suture-relay ASA and CSA groups (61.3 ± 6.5 and 57.5 ± 9.7 N, respectively) than in the loop-locking TTP group (38.3 ± 9.4 N; P < .05). The ultimate load to failure was significantly greater in the suture-relay ASA group than in the loop-locking TTP group (153 ± 55.1 N vs 102 ± 12.9 N; P < .05). All specimens in the loop-locking TTP group failed by suture elongation mode, whereas only 2 specimens (18%) in the suture-relay ASA group and 5 specimens (45%) in the CSA group failed by suture elongation. Nine specimens (82%) in the suture-relay ASA group and 6 specimens (55%) in the CSA group failed due to suture cutout through the meniscal tissue. The biomechanical properties after PMMR repair did not statistically differ between the suture-relay ASA and CSA groups. The suture-relay ASA technique had a higher load to failure than the loop-locking TTP technique. The suture-relay ASA technique is a promising option for the repair of PMMRTs; its repairing strength is also comparable to that of the CSA technique. Notably, the suture-relay ASA technique can be utilized without establishing a posteromedial portal, resulting in decreased procedure time and mitigating challenges associated with working from the posterior aspect of the knee.

Mid-term patient-reported outcomes are inferior in opening-wedge high tibial osteotomy patients with untreated medial meniscus posterior root tear.

The impact of untreated medial meniscus posterior root (MMPR) tear (MMPRT) during opening-wedge high tibial osteotomy (OWHTO) on patient-reported outcomes (PROs) remains poorly understood. This retrospective cohort study aimed to investigate the association between the presence of MMPRT and post-operative PROs in patients who underwent OWHTO. A total of 83 knees that underwent OWHTO that were followed up for 6.6 years were included. Post-operative PROs were assessed using the knee injury and osteoarthritis outcome score (KOOS) subscales. Medial meniscus extrusion (MME) was measured by magnetic resonance imaging (MRI). MMPRT was diagnosed based on preoperative MRI and intraoperative arthroscopy findings. The participants were categorized into the MMPRT and MMPR intact (MMPRI) groups, and their KOOS subscales were compared. Additionally, logistic regression analysis was conducted to explore the correlation between KOOS and MMPRT presence. In total, 29 out of 80 (36.3%) knees were classified into the MMPRT group, while three knees underwent total knee arthroplasty. Preoperative MME was 3.5 ± 1.9 (range 0-8.9) mm, showing correlation with the presence of MMPRT (p = 0.004) by regression analysis. The post-operative KOOS subscales of the MMPRT group were lower than the MMPRI group for pain (p = 0.017), activities of daily living (ADLs) (p = 0.001), sports (p < 0.001) and quality of life (QOL) (p < 0.001). Additionally, regression analysis showed the presence of MMPRT was correlated with lower KOOS subscale scores for pain (p = 0.041), ADLs (p = 0.011), sports (p < 0.001) and QOL (p = 0.002). Preoperative MMPRT correlated with a reduction in mid-term post-operative PROs, as assessed using the KOOS, among patients who underwent OWHTO. Surgeons should consider addressing an MMPRT at the time of OWHTO. Level IV.

Biomechanical comparison of ultra-high molecular weight polyethylene sutures of different thicknesses of the tensile strength for pullout repair of medial meniscal posterior root tear.

Medial meniscus posterior root tears (MMPRT) are a risk factor for knee osteoarthritis. The predominant treatment for MMPRT is transtibial pullout repair, and loop suture remains the gold standard procedure. This study aimed to investigate the structural properties of the meniscus-suture-tibia (MST) complex after loop stitch using ultra-high molecular weight polyethylene (UHMWPE) suture tape of different thicknesses. This study used 20 fresh porcine MMPRT model knees. All specimens were randomised into two treatment groups: (1) pullout repair using 1.3 mm suture tape (thin group, n = 10; 1.3 mm PERMATAPE, Mitek Sports Medicine) fixation and (2) pullout repair using 2.5 mm suture tape (thick group, n = 10; 2.5 mm PERMATAPE, Mitek Sports Medicine) fixation. The single-loop stitch MS technique was utilised. The MST complex specimens were placed on a tensile tester. The structural properties of the MST complex (yield load, maximum load, liner stiffness, and elongation at failure) were identified. No significant differences were found between the thin and thick groups in terms of maximum load (108.8 ± 49.6 vs. 90.1 ± 33.6 N; p = 0.34), yield load (43.8 ± 15.2 vs. 39.4 ± 15.5 N; p = 0.53), liner stiffness (12.6 ± 8.4 vs. 11.2 ± 5.5 N/mm; p = 0.45), and elongation at failure (27.1 ± 19.4 vs. 19.9 ± 10.0 mm; p = 0.32). The structural properties of the thickness of the different UHMWPE were comparable in MMPRT repair. Additionally, 1.3 mm PERMATAPE may demonstrate similar repair potential as 2.5 mm PERMATAPE. Level Ⅳ.

High tibial osteotomy on varus knee osteoarthritis with medial meniscus posterior root injury

To explore clinical effect of distal tibial tubercle-high tibial osteotomy (DTT-HTO) in treating knee osteoarthritis (KOA) with medial meniscus posterior root tear (MMPRT). A retrospective analysis was performed on 21 patients with varus KOA with MMPRT from May 2020 to December 2021, including 3 males and 18 females, aged from 49 to 75 years old with an average of (63.81±6.56) years old, the courses of disease ranged from 0.5 to 18.0 years with an average of(5.9±4.2) years, and 4 patients with grade Ⅱ, 14 patients with grade Ⅲ, and 3 patients with grade Ⅳ according to Kellgren-Lawrence;14 patients with type 1 and 7 patients with type 2 according to MMPRT damage classification. The distance of medial meniscusextrusion (MME) and weight-bearing line ratio (WBLR) of lower extremity were compared before and 12 months after operation. Visual analogue scale (VAS), Western Ontarioand and McMaster Universities (WOMAC) osteoarthritis index, and Lysholm knee score were used to evaluate knee pain and functional improvement before operation, 1, 6 and 12 months after operation, respectively. Twenty-one patients were followed up for 12 to 18 months with an average of (13.52±1.72) months. MME distance was improved from (4.99±1.05) mm before operation to (1.87±0.76) mm at 12 months after operation (P<0.05). WBLR was increased from (15.49±7.04)% before operation to (62.71±2.27)% at 12 months after operation (P<0.05). VAS was decreased from (7.00±1.14) before operation to (2.04±0.80), (0.90±0.62) and (0.61±0.50) at 1, 6 and 12 months after operation. WOMAC were decreased from preoperative (147.90±9.88) to postoperative (103.43±8.52), (74.00±9.54) and (47.62±9.53) at 1, 6 and 12 months, and the difference were statistically significant (P<0.05). Lysholm scores were increased from (46.04±7.34) before oepration to (63.19±8.93), (81.10±6.41) and (89.29±3.04) at 1, 6 and 12 months after operation(P<0.05). For the treatment of varus KOA with MMPRT, DTT-HTO could reduce medial meniscus protrusion distance, improve the ratio of lower limb force line, and effectively reduce knee pain and improve knee joint function.

Fast rehabilitation does not worsen clinical, radiological, and arthroscopic outcomes after medial meniscus posterior root repair: A retrospective comparative study

Background/ObjectiveThe main surgical treatment for medial meniscus posterior root tear (MMPRT) has shifted from meniscectomy to meniscus repair; however, there is no clear consensus regarding the optimal postoperative management strategy after MMPRT repair. This study aimed to perform a comparative analysis of patients who received conventional rehabilitation or fast rehabilitation following MMPRT repair. MethodsThe current retrospective cohort study compared clinical, radiological, and arthroscopic outcomes after conventional rehabilitation (group A, January 2020 to April 2020, 24 patients) with those after fast rehabilitation (group B, May 2020 to August 2020, 24 patients) in patients who underwent pullout repair for MMPRT. Partial weight-bearing and range of motion exercises were allowed 2 weeks postoperatively in group A and 1 week postoperatively in group B. In patients with an average weight of approximately 60 kg, full weight bearing was allowed 4 weeks postoperatively in group A and 3 weeks postoperatively in group B. ResultsAt 12 months postoperatively, the clinical scores, including International Knee Documentation Committee and Japanese Knee Injury and Osteoarthritis Outcome Score, significantly improved in both groups (p < 0.01). Although meniscus healing was achieved in both groups, medial meniscus extrusion significantly progressed by 0.9 mm in group A and 0.8 mm in group B (p < 0.01, compared with preoperative extrusion). There were no significant differences in clinical scores, arthroscopic meniscal healing status, or medial meniscus extrusion progression on magnetic resonance images between the groups. ConclusionA fast rehabilitation protocol can be safely implemented without compromising patient outcomes after pullout repair for MMPRT.

Partial weight-bearing and range of motion limitation significantly reduce the loads at medial meniscus posterior root repair sutures in a cadaveric biomechanical model.

The aim of this study was to investigate the influence of medial meniscus posterior root avulsion (MMPRA) before and after surgical treatment on the biomechanics of the knee joint, including suture repair forces during daily and crutch-assisted gait movements. MMPRA were investigated in eight human cadaver knee joint specimens by a dynamic knee joint simulator with daily (normal gait, gait with additional rotational movement, standing up, sitting down) and rehabilitation-associated movements (crutch-assisted gait with limited flexion range of motion [30°] and 30% [toe-touch weight-bearing, TTWB] and 50% of body weight [partial weight-bearing, PWB]) with simulated physiologic muscle forces. Each specimen was tested in intact, torn and repaired (transtibial suture) state. The biomechanical parameters were: medial mean contact pressure and area, knee joint kinematics, medial displacement of the posterior meniscus horn and loading on the anchoring suture. Significant reduction of the contact area due to the avulsion was observed in all movements except for PWB and sitting down. MMPRA repair significantly increased the contact areas during all movements, bringing them to levels statistically indistinguishable from the initial state. MMPRA resulted in a medial displacement up to 12.8 mm (sitting down) and could be reattached with a residual displacement ranging from 0.7 mm (PWB) to 5.7 mm (standing up), all significantly (p < 0.001) reduced compared to the torn state. The mean peak anchoring suture load increased from TTWB (77 N), PWB (91 N) to normal gait (194 N), gait rotation (207 N), sitting (201 N; p < 0.01) and to standing up (232 N; p = 0.03). Surgical treatment of MMPRA allows restoration of physiological knee joint biomechanics. Crutch-assisted movements reduce the loading of the repair suture, thus likewise the risk for failure. From a biomechanical point of view, crutch-assisted movements are recommended for the early rehabilitation phase after MMPRA repair. Level V.

Arthroscopic Centralization of the Medial Meniscus Reduces Load on a Posterior Root Repair Under Dynamic Varus Loading: A Biomechanical Investigation

Background: In addition to the integrity of the meniscal hoop function, both the anterior and posterior meniscus roots as well as the meniscotibial and meniscofemoral ligaments are crucial in restraining meniscal extrusion. However, the interaction and load sharing between the roots and these peripheral attachments (PAs) are not known. Purposes: To investigate the influence of an insufficiency of the PAs on the forces acting on a posterior medial meniscus root repair (PMMRR) in both neutral and varus alignment and to explore whether meniscal centralization reduces these forces. Study Design: Controlled laboratory study. Methods: In 8 fresh-frozen human cadaveric knees, an arthroscopic transosseous root repair (step 1) was performed after sectioning the posterior root of the medial meniscus. The pull-out suture was connected to a load cell to allow measurement of the forces acting on the root repair. A medial closing-wedge distal femoral osteotomy was performed to change the mechanical axis from neutral to 5° of varus alignment. The meniscus was completely released from its PAs (step 2), followed by transosseous arthroscopic centralization (step 3). Each step was tested in both neutral and varus alignment. The specimens were subjected to nondestructive dynamic varus loading under axial compression of 300 N in 0°, 15°, 30°, 45°, and 60° flexion. The changes in force acting on the PMMRR were statistically analyzed using a mixed linear model. Results: Axial loading in neutral alignment led to an increase of the force of root repair of 3.1 ± 3.1 N (in 0° flexion) to 6.3 ± 4.4 N (in 60° flexion). In varus alignment, forces increased significantly from 30° (3.5 N; 95% CI, 1.1-5.8 N; P = .01) to 60° (7.1 N; 95% CI, 2.7-11.5 N; P = .007) flexion, in comparison with neutral alignment. Cutting of the PAs in neutral alignment led to a significant increase of root repair forces in all flexion angles, from 7.0 N (95% CI, 1.0-13.0 N; P = .02) to 9.1 N (95% CI, 4.1-14.1 N; P = .003), in comparison with the intact state. Varus alignment significantly increased the forces in the cut states from 4.8 N (95% CI, 1.0-8.5 N; P = .02) to 11.1 N (95% CI, 4.2-18.0 N; P = .006) from 30° to 60° flexion, in comparison with the neutral alignment. Arthroscopic centralization led to restoration of the native forces in both neutral and varus alignment, with no significant differences between the centralized and intact states. Conclusion: An insufficiency of the PAs of the medial meniscus, as well as varus alignment, led to increased forces acting on a PMMRR. These forces were reduced via an arthroscopic meniscal centralization. Clinical Relevance: Performing arthroscopic meniscal centralization concomitantly with PMMRR may reduce failure of the repair by reducing the load of the root.

Medial meniscal posterior root tear – A current concept review

Menisci are crucial structures in the knee joint for the adequate distribution of hoop stresses. Their significance in preventing early knee osteoarthritis has been acknowledged due to the rapid progression of osteoarthritis in knees following meniscectomy. The anatomy of menisci has been studied in detail with an increased understanding of the importance of meniscal root attachments. This review aims to provide an evaluated summary of the anatomical, biochemical, and functional aspects that are relevant in the clinical context of meniscus root attachments, alongside contemporary strategies for accurately diagnosing and treating common injuries affecting these attachments. We also propose an algorithm for managing medial meniscus root tears which may be beneficial for the readers. We did an up-to-date literature search on PubMed, Scopus, and Google Scholar database, using the keywords ‘meniscus’, ‘meniscal root’, ‘sports injury’, and ‘arthroscopy’ in April 2024 and filtered out the relevant literature for this review on the articles that were published in English. The management of root tears requires a high level of suspicion which is crucial for diagnosis, identifying subtle signs on radiology, and employing specific methods for root repair. The tears or avulsions within one centimeter of the tibial attachment of the medial meniscus posterior root are called medial meniscus posterior root tears. These injuries cause a functional meniscal deficiency, resulting in knee problems unfavorable to biomechanics. Numerous methods have been created to tackle meniscus root tears., with many demonstrating promising outcomes in terms of complete healing.

Long-term Outcomes of Partial Meniscectomy for Degenerative Medial Meniscus Posterior Root Tears.

Previous studies have demonstrated that medial meniscus posterior root tear (MMPRT) repair is superior to debridement in terms of patient-reported outcomes, rates of conversion to total knee arthroplasty (TKA), and long-term costs. Despite the known poor midterm outcomes, there is a paucity of long-term results of partial meniscectomy for degenerative MMPRTs. To 1) evaluate long-term patient-reported and radiographic outcomes of patients who underwent partial medial meniscectomy (PMM) for MMPRTs, and 2) determine the rate of and risk factors for conversion to total knee TKA. Case series; Level of evidence, 4. A previously identified cohort of 26 patients treated with partial meniscectomy for isolated MMPRTs between 2005 and 2013 was prospectively followed for long-term outcomes at a minimum 10-year follow-up. Patients were evaluated for International Knee Documentation Committee (IKDC) outcome score, reoperation, and conversion to TKA. Failure was defined as conversion to arthroplasty or a severely abnormal IKDC subjective score <75.4. This study included 26 patients (10 men, 16 women; mean age, 54 ± 8.7 years [range, 38-71 years] at diagnosis; body mass index, 32.9 ± 5.5) who were followed for a mean of 14.0 ± 3.6 years (range, 10.1-19.6 years). At the final follow-up, 1 patient was deceased and 18 (72%) of the remaining 25 patients had progressed to TKA, with 1 (4%) patient undergoing repeat meniscectomy. The 6 (24%) patients who had not progressed to TKA or revision surgery reported a mean IKDC score of 57 ± 23. Nineteen patients underwent subsequent surgery and 5 demonstrated severely abnormal IKDC scores resulting in a clinical failure rate of 96% (24 of the 25 living patients) at a mean 14-year follow-up. PMM for medial meniscus posterior horn root tears demonstrated 72% progression to TKA and 96% failure according to subjective clinical outcomes at a minimum 10-year follow-up.