Medial Meniscal Root Repair Research Articles

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.

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.

Poster 234: Establishing the Minimal Clinically Important Difference and Patient Acceptable Symptomatic State After Isolated Arthroscopic Posterior Medial Meniscal Root Repair

Objectives: Root tears encompass avulsion injuries affecting the bony or soft tissue root attachments of the meniscus, as well as radial tears occurring within 1 cm of these attachment points. Meniscal root tears have been increasingly recognized as contributors to early onset osteoarthritis and disrupted joint kinematics and insights from animal, cadaveric, and clinical studies have resulted in a paradigm shift from meniscectomy towards repair. The purpose of this study is to define the minimal clinically important difference (MCID) and patient-acceptable symptomatic state (PASS) for patient-reported outcome measures (PROMs) following isolated posterior medial meniscal root repair (PMMR) and to investigate the role of preoperative, demographic, and intraoperative variables for predicting achievement of these thresholds. We hypothesized that patients have a greater likelihood of achieving MCID with lower preoperative outcome scores and a greater likelihood to achieve PASS with higher preoperative outcome scores. Furthermore, certain preoperative and intraoperative factors are likely to influence achievement of MCID and PASS following PMMR. Methods: This is an IRB approved retrospective study of prospectively collected data from a single, high-volume institution. Inclusion criteria were patients who underwent arthroscopic PMMR performed by one of three fellowship-trained attending surgeons with a minimum of two year postoperative follow up. Exclusion criteria consisted of patient with KL grade &gt;3 osteoarthritis and concomitant ligamentous procedures. Patients who had ipsilateral knee surgery within 2 years of undergoing meniscal root repair were also excluded. PROMs were collected from January 2017 to September 2023 and an electronic medical record was reviewed for demographic variables, intraoperative details, and postoperative complications. PROMs analyzed in this study include the International Knee Documentation Committee Score (IKDC), the Knee Injury and Osteoarthritis Outcome Score Jr. (KOOS Jr.) and the Veterans Rand 12 Physical Function (VR12 P). MCID was determined to be one-half the standard deviation of the difference from baseline in PROM scores at minimum two-year follow-up. PASS thresholds were calculated using an anchor-based approach. Receiver operating characteristic (ROC) analysis for the calculation of PASS was conducted and optimal thresholds were calculated using the Youden Index to maximize the sensitivity and specificity of threshold values. Multivariate logistic regression analyses were conducted to identify patient-related factors at baseline and intraoperative variables associated with the attainment of MCID and PASS. Results: Seventy patients were included in the final analysis. The demographics of included patients is listed in Table 1. The mean preoperative score, mean postoperative score, MCID threshold, MCID achievement rate, PASS threshold, and PASS achievement rate for IKDC, KOOS Jr., and VR12 physical are listed within Table 2. The predictive value for all PASS thresholds was good to excellent, with AUC values for IKDC, KOOS Jr., and VR12 Physical being 0.858, 0.864, and 0.755, respectively (Figure 1). For IKDC, lower BMI (OR 0.73, p = 0.03) and lower preoperative score (OR 0.94, p = 0.02) were predictive of MCID achievement, whereas lower BMI (OR 0.87, p &lt; 0.01) and greater preoperative score (OR 1.04, p = 0.04) were predictive of PASS achievement. For KOOS Jr., use of two sutures (OR 6.98, p &lt; 0.01) was predictive of MCID achievement, whereas use of two sutures (OR 6.91, p &lt; 0.01) and lower BMI (OR 0.81, p &lt; 0.01) were predictive of PASS achievement. For VR12 Physical scores, younger age (OR 0.92, p = 0.04), lower BMI (OR 0.84, p = 0.01), and lower preoperative score (OR 0.89, p &lt; 0.01) were predictive of MCID achievement, whereas use of two sutures (OR 7.24, p = 0.02), lower BMI (OR 0.92, p &lt; 0.01), and greater preoperative score (OR 1.19, p = 0.02) were predictive of PASS achievement. Conclusions: This study defines the thresholds for MCID and PASS achievement at minimum two-year follow-up for IKDC, KOOS Jr., and VR12 Physical scores in a large cohort of patients undergoing isolated posterior-medial meniscal root repair at a single, high-volume institution. More patients achieved MCID than PASS. Lower BMI, use of fewer sutures, and preoperative scores were the most common predictors of MCID and PASS achievement. Additionally, younger age was an independent predictor of MCID achievement for VR-12 Physical Function.

Clinical outcomes following transtibial medial meniscal root repair are maintained at long-term follow-up.

To evaluate long-term outcomes of patients treated with posterior medial meniscal root tear (PMMRT) repair through assessment of functional outcome scores and to identify patient surgical and magnetic resonance imaging (MRI) characteristics associated with improved outcomes. This was a single-centre, retrospective study evaluating patients who had undergone a PMMR repair using a transtibial suture pullout technique with two locking cinch sutures. This was performed as a follow-up to previously published 2-year and 5-year outcome studies, using the same cohort. All patients from the prior short-term and midterm studies were invited to participate. Patient-reported outcome (PROs) scores, including the International Knee Documentation Committee (IKDC) and Lysholm scores, were collected. Previously collected demographic data were updated based on review of the electronic medical record. Patient outcomes were assessed preoperatively, as well as at 2-year, 5-yearand 8-yearpostoperatively. MRI outcome measurements were assessed at 2-year and 5-year follow-ups. All statistical analysis was performed using SPSS version 26. Seventeen patients of the original 18 patients (94.4%) were included in the final analysis. Additionally, three patients who had additional ipsilateral surgery were excluded from the analysis of PROs. The IKDC score significantly increased from 44.7 ± 11.6 at preoperative baseline to 71.2 ± 21.3 at 8-yearpost-operation (p = 0.001). There were no significant differences in IKDC score between 2-year and 8-year follow-ups (p = n.s.) or 5-year and 8-year follow-ups (p = n.s.). The Lysholm score significantly increased from 49.6 ± 7.3 at preoperative baseline to 76.4 ± 17.2 at 8-year follow-up (p < 0.001). There was no significant difference in Lysholm scores between 2-year and 8-year follow-ups (p = n.s.) or 5-year and 8-year follow-ups (p = n.s.). A linear regression analysis found that 5-year IKDC scores were significantly correlated with 8-year IKDC scores (β = 0.681, p = 0.038). At 8-year follow-up, four (23.5%) patients required additional procedures on their operative knee (one total knee arthroplasty conversion). Patients treated with repair of PMMRT had maintenance of clinical outcome improvements at long-term follow-up despite worsening MRI outcomes at short-term and medium-term follow-ups. While a high proportion of patients required additional procedures on their operative knee at 8-yearfollow-up, few of these patient's additional procedures were related to failure of their primary surgery. Providers and patients may expect durable clinical outcomes following the repair of PMMRT, irrespective of radiographic appearance. Level IV.

Arthroscopic Medial Meniscal Root Repair Using a Novel Re-Tensionable All-Suture Anchor

Background: Medial meniscal root repairs are devastating injuries that can cause long-term knee problems if not properly addressed. Some common issues when addressing these injuries surgically include the “bungee-cord” effect seen with implants that sit too far from the tibial plateau surface and loss of tension on the sutures after cycling of the knee after the repair. This video will discuss the presentation of a patient with a medial meniscal root repair treated with a novel technique to counteract these aforementioned issues. Indications: Based on the patient’s medial meniscal root tear and minimal arthritis seen on radiograph, he was indicated for a meniscal root repair to prevent meniscal extrusion and reinforce normal meniscal hoop stresses to limit progression of his arthritis. Technique Description: This technique uses a novel re-tensionable all-suture anchor through a transtibial tunnel with 2 repair sutures through the meniscal root that sits just below the tibial plateau, allowing the surgeon the ability to re-tension the implant after cycling the knee. Results: Arthroscopic repair of the medial meniscal root allowed the patient to return to his previous level of activity. Discussion/Conclusion: In this case, arthroscopic medial meniscal root repair can yield good results in patients to get them back to their previous level of activity while minimizing the chance of rapid arthritic progression that is typically seen with nonoperative management of these injuries. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Tunnel Overlap Occurs 25% of the Time With Simultaneous Anterior Cruciate Ligament Reconstruction and Lateral Meniscal Root Repair

PurposeTo assess the risk of socket-tunnel overlap for posterior medial or lateral meniscal root repair combined with anterior cruciate ligament reconstruction (ACLR) using artificial tibias and computerized tomography (CT) scans for three-dimensional (3D) modeling. MethodsArtificial tibias (n=27; n=3/subgroup) were allocated to groups based on inclination of socket-tunnels (550, 600, 650) created for MMPR and LMPR repair, and ACLR. Three standardized socket-tunnels were created: one for the ACL and one for each posterior meniscal root insertion. CT scans were performed and sequentially processed using computer software to produce 3D models for assessment of socket-tunnel overlap. Statistical analysis was performed with Kruskal-Wallis and Mann-Whitney U tests. Significance was set at p<0.05. ResultsThe present study found no significant risk of tunnel overlap when drilling for combined ACLR and MMPR repair, while seven cases of tunnel overlap occurred between ACL tunnels and LMPR (25.9% of cases). No subgroup or specific pattern of angulation consistently presented significantly safer distances than other subgroups for all distances measured. ConclusionThis study demonstrated 25.9% rate of overlap for combined LMPR repair and ACLR, compared to 0% for MMPR repair with ACLR. Lower ACL drilling angle (55 or 60 degrees) combined with higher lateral meniscus drilling angle (65 degrees) produced no socket-tunnel overlap. Clinical RelevanceSocket-tunnel overlap during meniscal root repair combined with ACLR may compromise graft integrity and lead to impaired fixation and treatment failure of either the ACL, the meniscus, or both. Despite this, risk for socket-tunnel overlap has not been well characterized.

Podium Presentation Title: MCL Pie-Crusting During Isolated Medial Meniscal Root Repair Leads to Improved Outcomes

Podium Presentation Title: MCL Pie-Crusting During Isolated Medial Meniscal Root Repair Leads to Improved Outcomes

Arthroscopic pullout repair versus suture anchor repair for medial meniscus posterior root tear combined with high tibial osteotomy

BackgroundThe aim of this study was to compare the outcomes of pullout repair with a metal button and suture anchor repair for medial meniscus posterior root tears in patients undergoing high tibial osteotomy with varus alignment. MethodsPatients who underwent arthroscopic pullout repair (P group) and suture anchor repair (SA group) in combination with open-wedge high tibial osteotomy between 2018 and 2021 were retrospectively examined. Patients who received second-look arthroscopy at 1 year and at least 2 years of follow up were included. Structural healing (complete/partial or failed healing) and chondral lesions at the initial surgery and the second-look arthroscopy, radiographic parameters around the knee, Lysholm score, and Tegner activity scale (before and 2 years after surgery) were compared. ResultsA total of 88 patients (68 women/20 men, mean age 61.1 ± 7.9 years old) were included in the analysis. Of these, 51 patients underwent pullout repair, while the other 37 underwent suture anchor repair. The SA group showed a significantly higher rate of complete healing (64.9%) than the P group (21.6%, P < 0.001). The Lysholm score significantly improved after surgery in both treatment groups. At the final follow up, the SA group had a significantly higher Lysholm score (89.6 ± 10.7) than the P group (80.9 ± 17.4, P = 0.011). ConclusionArthroscopic suture anchor repair had superior healing status and Lysholm Score in comparison with pullout repair with a metal button, as it achieved better tension adjustment. This result is meaningful particularly when medial meniscus root repair and high tibial osteotomy are performed simultaneously.

Satisfactory Clinical Outcome, Complications, and Provisional Results of Meniscus Centralization with Medial Meniscus Root Repair for the Extruded Medial Meniscus at Mean 2-Year Follow-Up

To describe the patient-reported clinical outcomes following medial meniscus root repair with meniscus centralization and to identify common complications and detail provisional results. Patients undergoing medial meniscus root repair with meniscus centralization from 2020 to 2022 were identified using an institutional database. Patients were followed prospectively using postoperative Tegner Activity Scale, visual analog scale (VAS) for pain, Knee Injury and Osteoarthritis Outcome Score, Joint Replacement, International Knee Documentation Committee score, and a Likert score for improvement, surgery satisfaction, and subsequent surgeries at minimum 1-year follow-up with mean 2-year follow-up. Demographics, injury characteristics, and surgical details were also collected. Twenty-five patients (age: 50 ± 11 years; sex: 76% female; body mass index: 33 ± 8) were included in this study. Postoperative Tegner score was maintained at preoperative levels (P= .233), and VAS at rest, VAS with use, Knee Injury and Osteoarthritis Outcome Score, Joint Replacement, and International Knee Documentation Committee improved significantly postoperatively (P= .003; P < .001, P < .001, P= .023, respectively). Eighty-eight percent of patients reported subjective improvement in their knee at final follow-up. Postoperative radiographs did not show any significant osteoarthritis progression, and no patients had undergone a revision meniscus surgery or total knee arthroplasty at the time of follow-up. At minimum 1-year follow-up and mean 2-year follow-up, patients undergoing medial meniscus root repair with meniscus centralization demonstrated significant postoperative improvements in pain, function, and quality of life and reported high rates of surgery satisfaction. There was no evidence of significant arthritic progression on postoperative imaging, and no patients underwent revision meniscus surgery or total knee arthroplasty. Level IV, case series.

Biomechanical Analysis of Meniscotibial Ligament Tenodesis to Treat Meniscal Extrusion in the Setting of Posterior Medial Meniscus Root Repair

Background: Meniscal extrusion often persists after a medial meniscus root repair. If the meniscus is extruded, the function of the meniscus as a load-sharing device and secondary knee stabilizer is compromised. Hypothesis: It was hypothesized that repairing the meniscotibial ligament (MTL) would decrease meniscal extrusion in the settings of both an isolated MTL tear and a repaired medial meniscus root while also improving medial compartment contact mechanics. Study Design: Controlled laboratory study. Methods: Ten fresh-frozen cadaveric knees (mean age, 50.5 years) were tested in 5 conditions: intact, MTL deficiency, MTL deficiency + posterior medial meniscus root deficiency, MTL deficiency + posterior medial meniscus root repair, and MTL tenodesis + posterior medial meniscus root repair. Specimens were mounted to a load frame that applied a 1000-N axial load. Joint contact pressures were measured using thin pressure sensors, and the peak and mean pressures were analyzed. Ultrasound was used to measure meniscal extrusion. Results: The MTL tear in isolation resulted in significant meniscal extrusion compared with the intact state (P = 0.035) without a detectable difference in medial compartment pressures. The addition of a root tear to the MTL tear state resulted in significantly more extrusion (P = 0.001) and significant increases in medial compartment pressure (P = .030) compared to the MTL tear state. Root repair alone restored extrusion, mean contact pressure, and peak contact pressure back to the intact state (P > .05). Conclusion: This study showed that MTL disruption led to increased meniscal extrusion in a cadaveric model. Unlike the root tear state, MTL disruption did not change contact mechanics. Furthermore, root repair alone was sufficient in restoring intact biomechanics and extrusion. Clinical Relevance: This study may help clinicians understand the origin of medial meniscus root tears and aid in the decision-making process for whether to add an MTL tenodesis in the setting of root repair.

An Antegrade Soft Anchor in a Retrograde Drilling for Medial Meniscus Root Repair with High Tibial Osteotomy: A Modified Approach to Avoid Tunnel Collision

An Antegrade Soft Anchor in a Retrograde Drilling for Medial Meniscus Root Repair with High Tibial Osteotomy: A Modified Approach to Avoid Tunnel Collision

Medial Collateral Ligament Pie-Crusting for Isolated Medial Meniscal Root Repair Is Associated With Improved Clinical Outcomes with Minimum 2-Year Follow-Up

To determine clinical and radiographic outcomes of medial collateral ligament (MCL) pie-crusting during isolated medial meniscal root repair. A retrospective review was conducted between August 2013 and December 2019 in patients undergoing isolated medial meniscal root repair. Outcomes, including International Knee Documentation Committee (IKDC) score, Lysholm score, re-tears, MCL laxity, and conversion to total knee arthroplasty (TKA), were compared between pie crust (PC) and non-pie crust (NPC) cohorts. Other assessments included subjective instability or stiffness, infection, and intra-operative chondromalacia. Additionally, radiographic outcomes were compared to determine progression of medial compartment arthrosis. Final analysis included 97 knees, 45 in the PC, and 52 in the NPC group. IKDC and Lysholm scores were similar between both groups preoperatively and 3 months postoperatively. However, at the 6,12, and 24-month follow up, the PC group had a significantly higher measured IKDC and Lysholm scores than the NPC group. PASS percentages for the IKDC score were significantly higher in the PC group at 6 months, 1 year, and 2 years (96.2%; P= .02) follow-up compared to the NPC group. MCID percentages for the IKDC score were also significantly higher at the 1- and 2-year (100%; P= .05) follow-up in the PC group compared to the NPC group. There was also a significantly higher rate of recurrent medial meniscal root tears in the NPC group (4 [8.9%]) compared to the PC group (0 [P= .03]). No MCL laxity was observed at 6 months follow-up. MCL pie-crusting during isolated medial meniscal root repair can be used as an alternative surgical technique, as it leads to improved clinical and patient outcomes compared to patients who do not undergo MCL pie-crusting in the short term. Additionally, those that underwent MCL pie-crusting had a lower incidence of recurrent tears, and no patients experienced MCL laxity at 6 months. Level III, retrospective cohort/comparative study.

Poster 134: Biomechanical Analysis of Meniscotibial Ligament Tenodesis to Treat Meniscal Extrusion in the Setting of Posterior Medial Meniscal Root Repair

Poster 134: Biomechanical Analysis of Meniscotibial Ligament Tenodesis to Treat Meniscal Extrusion in the Setting of Posterior Medial Meniscal Root Repair

Concomitant Medial Meniscal Root Repair with Extrusion Repair (Centralization Technique).

Concomitant Medial Meniscal Root Repair with Extrusion Repair (Centralization Technique).

Poster 239: Advanced Patellofemoral Chondromalacia Does Not Affect Outcomes After Meniscal Root Repair

Objectives: Meniscal root tears have been shown to accelerate cartilage breakdown and increase the risk of total knee arthroplasty (TKA) if left unaddressed. Unfortunately, many patients with meniscal root tears already have associated chondromalacia which can impact surgical outcomes. The presence of advanced chondromalacia in the medial or lateral compartmentsof the knee is a known contraindication to performing meniscal root repair; however, the effect of advanced patellofemoral chondromalacia on meniscal root outcomes is not known. The purpose of this study was to compare the outcomes of meniscal root repair in patients with and without advanced patellofemoral chondromalacia (PFC). Methods: A retrospective review of prospectively collected data of patients undergoing meniscal root repair by a single surgeon was conducted between January 2016 and December 2019. Patients were included if they had undergone an isolated posterior medial or lateral meniscal root repair. The meniscal root repair was performed using a transtibial suture technique. Patients were placed into one of two groups depending on the amount of patellofemoral chondromalacia present at the time of surgery. Patients with Outerbridge grade 0-2 were placed in the Minimal Patellofemoral Chondromalacia (MPFC) Group. Patients with Outerbridge 3-4 changes found the time of surgery were placed in the Patellofemoral Chondromalacia (PFC) Group. Patients with Outerbridge 3-4 changes found in the medial or lateral compartment were excluded from the study. Lysholm Knee Scoring Scale and the International Knee Documentation (IKDC) Subjective Knee Form were collected preoperatively, 6,12 and 24 months after surgery. Clinical outcomes followed included recurrent meniscal tear, conversion to total knee arthroplasty, knee arthrofibrosis requiring manipulation under anesthesia/lysis of adhesions and infection. PASS and MCID were determined using data on meniscal repairs in other literature. Continuous data was compared using two-tailed student-T test while categorical data was compared utilizing chi-square testing. Results: A total of 27 patients made up the PFC group and 54 in the MPFC group. There was no difference between the groups with regards to age, sex, BMI or laterality of the procedure. The PFC group had 26 medial and 1 lateral meniscal root repairs. The MPFC group had 51 medial and 3 lateral repairs. The average Outerbridge score of the patella for the PFC group was 3.2 compared to 1.8 in the MPFC group (p&lt;.001). The Outerbridge score for the trochlea in each group was 3.4 vs. 1.6 for the PFC and MPFC groups respectively (p&lt;.001). No difference was identified between the Outerbridge score for the medial compartment for the PFC and MPFC groups (1.48 vs 1.46 respectively) or the lateral compartments (0.48 vs. 0.61 respectively). Lysholm and IKDC scores rose significantly over the pre- operative value at all time points in the study for both groups. No difference was seen between the two groups for the Lysholm or IKDC scores at any timepoint during study. PASS rates for IKDC between the two groups were similar with 6,12 and 24-month PASS rates being 66.7%, 87.5% and 81.4% respectively for the PFC group and 62.9%, 77.8% and 85.2% for the MPFC group. There was also no difference between the groups with regards to the percentage of patients reaching MCID for IKDC. The PFC group showed the percentage of patients reaching MCID to be 81.5%, 100% and 92.6% at the 6,12, and 24 month time points respectively while the MPFC group showed the percentage of patients reaching MCID to be 75.9%, 88.9% and 94.4% at the 6,12 and 24 month postoperative time points respectively. There was 1 (3.7%) recurrent tear in the PFC group and 3 (5.6%) in the MPFC group (p=.72). One patient (3.7%) in the PFC and none of the MPFC group were converted to TKA by the 2-year follow up (p=.15). Each group had 1 patient develop arthrofibrosis requiring MUA/LOA. There were no infections in the PFC group and one in the MPFC group which was a superficial wound infection that resolved after a course of oral antibiotics. Conclusions: In our series, the presence of advanced patellofemoral chondromalacia did not lead to inferior short-term outcomes in patients undergoing meniscal root repair compared to patients without patellofemoral chondromalacia. IKDC and Lysholm scores were similar between the PFC and MPFC group at all time points while scores for both groups were significantly higher than preoperative levels at all time points. The ability to reach MCID and PASS for IKDC was not significantly different between the two groups. In addition, there was not a significant difference between the two groups in the number of recurrent tears, conversion to total knee arthroplasty or complications identified. Our results show meniscal root repair can be performed in patients with severe patellofemoral chondromalacia with similar results as patients undergoing root repair without severe patellofemoral chondromalacia. Patellofemoral chondromalacia should not be considered a contraindication to meniscal root repair.

Poster 264: Medial Tibia Bone Marrow Edema on Preoperative MRI Predicts Inferior Patient Outcomes Following Posterior Medial Meniscus Root Repair

Objectives: Repair of posterior medial meniscus root (PMMR) tears demonstrates favorable patient outcomes and may prevent rapid progression of knee osteoarthritis, however, there is a paucity of data in literature regarding prognostic factors affecting postoperative outcomes. The medial meniscus plays an important role in the knee biomechanically by increasing tibiofemoral contact area and decreasing peak tibiofemoral contact pressures. Few studies exist that examine preoperative knee magnetic resonance imaging (MRI) findings and patient reported outcome measures (PROMs) following PMMR repair. Semi-quantitative MRI evaluation can offer improved detection of degenerative pathology. Identifying specific factors that may predict surgical outcomes is important when considering PMMR repair, as some patients with more advanced degenerative joint disease may benefit from consideration for knee arthroplasty instead of joint preservation with meniscus repair surgery. The purpose of this study was to identify factors on preoperative MRI that may predict postoperative outcomes following PMMR repair. We hypothesize that patients with worse knee overall quality would have worse postoperative PRO scores. Methods: Between 2012 and 2020, patients who underwent posterior medial meniscus root repair at a tertiary referral academic center by fellowship trained sports medicine surgeons were retrospectively identified, recruited, and enrolled in the study. Institutional review board approval and informed consent was obtained. Inclusion criteria included patients ages 18-70, posterior medial meniscus root repair through transtibial fixation technique, minimum two years postoperative follow-up, and a preoperative knee MRI. Exclusion criteria included prior ipsilateral knee meniscus or ligamentous injury, additional ipsilateral knee injury requiring surgery, and conversion to knee arthroplasty. Visual Analog Scale (VAS) pain and PRO surveys including Patient Reported Outcome Measures Information System Physical Function (PROMIS-PF) Computer Adaptive Test, Lysholm Knee Score, Knee Osteoarthritis and Injury Outcome Score (KOOS) with 5 sub-sections, were collected at minimum 2-years postoperative. Patient Acceptable State Score (PASS) values from a prior meniscus study were utilized to identify patients that met PASS for the KOOS subsections. A fellowship-trained musculoskeletal radiologist reviewed preoperative MRIs and calculated Whole Organ Magnetic Resonance Imaging Scores (WORMS) for meniscus, cartilage, bone marrow edema pattern (BMEP) in 6 knee locations as well as effusion/synovitis and meniscal extrusion. Radiographs were scored with Kellgren-Lawrence (KL) scores to assess presence and severity of osteoarthritis. Statistical analysis was performed with Stata (StataCorp) using two sample T-tests, Mann-Whitney, and Fisher’s exact test for categorical variables. Significance was defined as p&lt;0.05. Results: We evaluated 29 knees (22 female patients) with a mean age at surgery of 52.3±9.9 years, body mass index of 27.6±5.6 kg/m2, and at a mean follow-up of 59.6 months ± 26.5. median KL grade 2, and 44.8% with meniscal extrusion. Pain scores decreased significantly from before surgery to final follow-up (p&lt;0.001), and the percentage of patients meeting PASS ranged from 44.8% for KOOS-Sport subscale to 72.4% for KOOS-Pain and KOOS-Quality of Life subscales (Table 1). There were 10 patients with medial tibial BMEP on pre-operative MRI and 19 with no medial tibial BMEP (Table 2). Patients with medial tibia BMEP had significantly lower Lysholm Knee Score (p=0.037), KOOS-Symptoms (p=0.028), and KOOS-QOL (p=0.029) (Figure 1). There were no significant differences in demographics between those with and without medial tibia BMEP. There was no significant difference in PRO scores when comparing those with medial femoral condyle BMEP, cartilage quality in any of the knee regions, or presence of meniscus extrusion. Conclusions: We observed that patients with medial tibia BMEP at baseline on their preoperative MRI had inferior PROMs for Lysholm Knee Score, KOOS Symptoms, and KOOS-QOL after PMMR repair compared to those without medial tibia BMEP. The presence of medial tibial BMEP could represent underlying damage that may not be evident in the cartilage itself, given most medial tibia cartilage was normal on MRI and cartilage quality was not a significant discriminant for outcomes. The presence of meniscus extrusion did not correlate with patient outcomes either. Limitations of this study include only VAS-Pain score as a pre-operative measure. Multivariate analysis was not possible due to the sample size available. A strength of this study is the mean follow up of approximately 5 years and preoperative MRI data on all patients. Posterior medial meniscus root tears are generally treated with surgical repair due to increased risk of progression to arthritis, however, some patients continue to have symptoms after repair. Our results show that patients with medial tibial BMEP on their preoperative MRI have worse PRO scores after posterior medial meniscus root repair, which can help surgeons better counsel patients towards optimal treatment options. In conclusion, the presence of medial tibia BMEP on preoperative MRI was a marker for inferior patient outcomes for Lysholm Knee Score, KOOS Symptoms, and QOL at minimum two years postoperative following posterior medial meniscus root repair. [Table: see text][Table: see text]

A Systematic Review of Adverse Events and Complications After Isolated Posterior Medial Meniscus Root Repairs

Background: Medial meniscus posterior root (MMPR) tears are recognized as a substantial cause of disability and morbidity. However, meniscus root repair, regardless of technique, is not without potential complications. Purpose: To evaluate the reported incidence of complications and adverse events after isolated MMPR repair. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using Embase, PubMed, and Scopus databases with the following search terms combined with Boolean operators: “meniscus,”“root,” and “repair.” Inclusion criteria consisted of level 1 to 4 human clinical studies in English or English-language translation reporting complications and adverse events after isolated posterior medial meniscus root repairs. The overall incidence of specific complications was estimated from the pooled sample of the included studies. Results: Eleven studies with a total pooled sample of 442 patients were identified. The mean patient age was 58.1 years, while the mean final follow-up time was 37.2 months (range, 12-84.8 months). The overall incidence of complications was 9.7% (n = 43/442), with the most commonly reported complication being progressive degenerative changes within the knee (10.4%; n = 25/240; n = 5 studies). A total of 1.25% (n = 3/240) of patients who experienced degenerative changes required conversion to total knee arthroplasty. Repair failures were reported in 3.1% (n = 10/327; n = 8 studies) of patients. Conclusion: Repairing MMPR tears is critical in preventing accelerated progression of knee osteoarthritis in patients without significant knee osteoarthritis preoperatively. While this repair is still recommended and necessary in appropriate patients, this review found that the incidence of complications after isolated posterior medial meniscus root repair was 9.7%, primarily involving the presence of progressive degeneration, while repair failure was reported in 3% of patients.

Repair of meniscus root tear - Is there a difference between medial meniscus root repair and lateral meniscus root repair? A systematic review and meta-analysis.

Complete meniscus root tear is associated with meniscus extrusion; this causes a loss of meniscus function and accelerated osteoarthritis of the knee. Existing small-scale retrospective case-control studies suggested that the outcomes were different between medial and lateral meniscus root repair. This meta-analysis aims to study whether such discrepancies exist via a systematic review of the available evidence in the literature. Studies evaluating the outcomes of surgical repair of posterior meniscus root tears, with reassessment MRI or second-look arthroscopy, were identified through a systematic search of PubMed, Embase, and Cochrane Library. The degree of meniscus extrusion, healing status of the repaired meniscus root, and functional outcome scores after repair were the outcomes of interest. Among the 732 studies identified, 20 studies were included in this systematic review. 624 knees and 122 knees underwent MMPRT and LMPRT repair, respectively. The amount of meniscus extrusion following MMPRT repair was 3.8 ± 1.7mm, which was significantly larger than the 0.9 ± 1.2mm observed after LMPRT repair (p < 0.001). Significantly better healing outcomes were observed on reassessment MRI after LMPRT repair (p < 0.001). The postoperative Lysholm score and IKDC score was also significantly better after LMPRT than MMPRT repair (p < 0.001). LMPRT repairs resulted in significantly less meniscus extrusion, substantially better healing outcomes on MRI, and superior Lysholm/IKDC scores, when compared to MMPRT repair. This is the first meta-analysis we are aware of that systematically reviews the differences in the clinical, radiographic, and arthroscopic results of MMPRT and LMPRT repair.

Opening-Wedge Distal Femoral Osteotomy With Concomitant Medial Meniscal Root Repair

Background: Valgus malalignment leads to excessive loading of the lateral compartment and has been associated with lateral compartment meniscal injuries and early-onset knee osteoarthritis. Distal femoral osteotomy (DFO) is a treatment option that allows correction of the mechanical access to offload the lateral compartment. Lateral opening-wedge distal femoral osteotomy and medial meniscal root repairs are both aimed to address the pathologic biomechanics of the tibiofemoral joint and when successful can delay or even prevent progression to end-stage osteoarthritic changes in the lateral and medial compartment, respectively. Indications: Distal femoral osteotomy is indicated for patients with normal metabolic bone health and valgus malalignment who may present with concurrent lateral meniscal injury, symptomatic lateral compartment arthritis, or a chronic medial collateral ligament tear/laxity. Technique Description: Long-leg alignment radiographs and preoperative magnetic resonance images are required to evaluate the degree of mechanical access deviation and to evaluate for soft tissue injury, as there is often concomitant lateral meniscal or cartilage pathology present. This technique demonstrates the optimal order of surgical steps for DFO with a concurrent medial meniscal root repair. The senior author’s preferred order is to first perform the open lateral approach and expose the lateral cortex for the placement of plate prior to arthroscopic work and excess fluid extravasation. Intra-articular work is then performed with a diagnostic arthroscopy followed by medial meniscal root repair. Finally, the osteotomy and subsequent internal fixation are performed. Results: The literature on opening-wedge DFO outcomes is heterogeneous, with variable rates of successful outcomes and complications. Saithna et al reported that International Knee Documentation Committee and the pain subdomain of Knee injury and Osteoarthritis Outcome Scores significantly improved postoperatively following lateral opening-wedge DFOs in patients with lateral compartment osteoarthritis. The 10-year success rate of varus-producing DFO has been reported to be 64% to 85%. Discussion: We describe a technique for correction of a valgus deformity with opening-wedge DFO and concurrent meniscal root repair. This surgical technique effectively restores the native femoral and tibial axis with appropriate load distribution and also concurrently restores the appropriate function of the medial meniscus which allows axial force dispersion via hoop stresses for the medial compartment. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

The Efficacy of High Tibial Osteotomy with or without Post-root Medial Meniscus Repair: A Systematic Review

Background: High tibial osteotomy (HTO) is a knee joint treatment modality for medial compartment arthritis, aiming to improve articular cartilage healing by shifting the lower limb’s axis. It is commonly used in younger patients with pain and active lifestyles, preventing advanced cartilage deterioration. Varus malalignment may often be accompanied with medial meniscus root tears. In recent years, meniscus root tears are often been repaired. However, the efficacy of medial meniscus repairs with high tibial in varus malalignment with medial meniscal tears remains a controversy. Purpose: The purpose is to study the functional outcomes of concurrent medial meniscus root repair with HTO versus HTO alone. Study design: Systematic review. Methods: According to Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines, we searched PubMed, Embase, Web of Science, and the Cochrane Library databases for studies reporting the outcomes of medial meniscus posterior root tear (MMPRT) repair with HTO versus HTO alone and extracted data about characteristics of patients, clinical functional scores, and radiologic outcomes. One reviewer extracted data and 1 reviewer assessed the risk of bias and performed a synthesis of the evidence. Articles were eligible if they reported the functional outcome of HTO alone or HTO and MMPRT repair in patients of varus malalignment and medial meniscus root tears. Results: 6 studies with 264 patients were identified. Data from these studies were segregated in HTO only and HTO with medial meniscus repair group. The findings of this systematic review suggest that the outcomes of HTO with MMPHRR and of only HTO are not statistically significant, meaning that doing valgus osteotomy only in patients with varus knee and MMPHRT can give good results regardless of not repairing the meniscus. Conclusion: HTO with medial meniscus posterior horn root repair seems to have no significant improvement in the functional outcomes of the patient. However, long-term studies need to be performed. Keywords: High tibial osteotomy, medial meniscus, root repair, arthroscopy, varus malalignment, meniscus, root tear