Meniscal Allograft Transplantation Research Articles

The Potential of Tendon Autograft as Meniscus substitution: Current concepts

Meniscectomy is known to alter the mechanics, stability, and kinematics of the tibiofemoral joint, leading to early knee osteoarthritis (KOA). While several meniscal substitutions exist, such as meniscus allograft transplantation, collagen meniscus implants, and artificial substitutes, they often come with technical challenges, high costs, and risks, including allograft failure, infections, and disease transmission. Tendon autografts emerge as a promising option, offering safety, availability, biocompatibility, and a reduced risk of pathophoresis.This review delves into basic, in vivo, in vitro, and biomechanical studies alongside clinical outcomes and future prospects of tendon autografts as meniscus substitutes. A thorough understanding of this option is vital for integrating these evolving techniques into clinical practice and mitigating early KOA progression.

Addressing meniscal deficiency part 1: An umbrella review of systematic reviews and meta‐analyses on meniscal allograft transplantation

AbstractPurposeMeniscal injuries are common in the young and active population. There is increasing utilization of surgical interventions like meniscal allograft transplantation (MAT) to restore the protective function of menisci following injury leading to meniscal deficiency. Extensive research and publications exist on the management of meniscal injury and the sequalae of meniscal deficiency. However, a comprehensive synthesis of the existing evidence through an umbrella review is lacking. This study aims to fill this gap by providing a current examination of the literature on MAT.MethodsA comprehensive search was conducted in the MEDLINE, Embase and Scopus databases to identify relevant systematic reviews and meta‐analyses. Studies were screened based on predefined inclusion and exclusion criteria. The quality of the included studies was assessed using the AMSTAR‐2 tool.ResultsA total of 41 studies were included in the review, with most published within the last decade. The majority of studies (56.1%) received a ‘Critically Low’ confidence rating, 26.8% were rated as ‘Low’, and only 14.6% were rated as ‘High’ confidence. From the included studies, 51.2% reported on PROMs, with the Lysholm score being the most common. Transplant failure and reoperation rate were reported in 34.1% and 19.5% of studies respectively. Studies on MAT reported favourable short‐term outcomes in terms of patient‐reported outcome measures (PROMs) but were limited by the lack of randomized control trials and consistent comparison groups.ConclusionsThis umbrella review highlights an increase in interest in MAT but underscores the need for higher‐quality reviews with standardized reporting and rigorous methodologies. Future research should focus on long‐term outcomes, optimal surgical techniques, patient selection criteria and risk factors for transplant failure. There is also a need for more studies focusing on MAT in pediatric populations. Overall, this review provides a comprehensive assessment of the current state of research in MAT and identifies areas for improvement in future studies.Level of EvidenceLevel IV.

Initial Outcomes following Fresh Meniscus Allograft Transplantation in the Knee.

Based on recent evidence-based advances in meniscus allograft transplantation (MAT), fresh (viable) meniscus allografts have a potential for mitigating key risk factors associated with MAT failure, and preclinical and clinical data have verified the safety of fresh meniscus allografts as well as possible efficacy advantages compared to fresh-frozen meniscus allografts. The objective of this study was to prospectively assess clinical outcomes for the initial cohort of patients undergoing MAT using fresh meniscus allografts at our center. Patients who were prospectively enrolled in a dedicated registry were included for analyses when they had undergone primary MAT using a fresh meniscus allograft for treatment of medial and/or lateral meniscus deficiency with at least 1-year follow-up data recorded. Forty-five patients with a mean final follow-up of 47.8 months (range = 12-90) were analyzed. Mean patient age was 30.7 years (range = 15-60), mean BMI was 29.7 kg/m2 (range = 19-48), and 14 patients (31%) were female. In total, 28 medial, 13 lateral, and 4 combined medial and lateral MATs with 23 concurrent ligament reconstructions and 2 concurrent osteotomies were included. No local or systemic adverse events or complications related to MAT were reported for any patient in the study. Treatment success rate for all patients combined was 91.1% with 3 patients requiring MAT revision and 1 patient requiring arthroplasty. Treatment failures occurred 8 to 34 months after MAT and all involved the medial meniscus. None of the variables assessed were significantly different between treatment success versus treatment failure cohorts. Taken together, the data suggest that the use of fresh (viable) meniscus allografts can be considered a safe and effective option for medial and lateral meniscus allograft transplantation. When transplanted using double bone plug suspensory fixation with meniscotibial ligament reconstruction, fresh MATs were associated with a 91% success rate, absence of local or systemic adverse events or complications, and statistically significant and clinically meaningful improvements in patient-reported measures of pain and function at a mean of 4 years postoperatively.

Low Rates of 30-Day Postoperative Complications After Meniscal Allograft Transplantation: A Retrospective Study Using the National Surgical Quality Improvement Program Database

PurposeThe purpose of this study is to determine the short-term (30-day) postoperative complication rates in patients undergoing meniscus allograft transplantation (MAT). MethodsAmerican College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database was queried for patients who had undergone MAT from 2014 to 2021 using Current Procedural Terminology (CPT) codes. Patients were excluded if they did not have sufficient demographic data – namely those without data for age, sex, BMI, preoperative functional status, ASA classification, operative time, and length of hospital stay. Post-operative complications within 30 days were identified and rates of complications were examined as the primary outcome of this study. As a secondary outcome, multivariate logistic regression was used to identify risk factors associated with the thirty-day incidence of post-operative complications. Subgroup analysis was performed to analyze differences in postoperative outcomes following isolated MAT versus MAT with concomitant ligament reconstruction/repair, cartilage preservation, or realignment osteotomy. ResultsA total of 396 meniscal transplants were identified, with mean age of 35.2 ± 14.9, mean body mass index (BMI) of 29.6 ± 6.7, mean length of stay of 0.5 ± 1.8 days. 11 patients experienced any adverse event (AAE), Specific complications included surgical site infections (5), deep vein thrombosis (DVT) (1), urinary tract infection (UTI) (3), and return to the operating room (OR) (2). On subgroup analysis, there was no significant difference between AAE rates in patients undergoing MAT with concomitant procedures compared to patients undergoing isolated MAT (7 vs 4, p=0.5). ConclusionPatients who underwent MAT had an overall complication rate of 2.8% in the short-term postoperative period (≤30 days). Patients undergoing MAT with concomitant ligament reconstruction/repair, cartilage preservation, and realignment osteotomy had similar rates of all postoperative complications when compared to patients undergoing isolated MAT. Level of EvidenceLevel IV, therapeutic case series.

Long-Term Results of Meniscus Allograft Transplantation With Bone Fixation Show Improved Outcomes but Progression of Joint Space Narrowing, Osteoarthritis, and Cartilage Degeneration

PurposeTo investigate the clinical and objective outcomes of meniscal allograft transplantation (MAT) using bone fixation in patients after a minimum follow-up duration of 15 years, and to compare the demographic factors and allograft status between patients who experienced progression of osteoarthritis and those who did not. MethodsThe consecutive patients who underwent primary MAT between December 1996 and January 2008 were retrospectively reviewed. The inclusion criteria was primary MAT with a minimum follow-up duration of 15 years. Clinical outcomes were evaluated using the modified Lysholm score, along with an evaluation of clinical failure. In objective outcomes, the progression of joint space narrowing, osteoarthritis, and the status of the associated cartilages and allografts were evaluated with follow-up radiographs and MRI. ResultsAmong the 79 cases, 54 knees in 52 patients were included in the study and evaluated for clinical outcomes. The mean Lysholm score improved from 73.9 ± 17.5 preoperatively to 86.4 ± 15.6 over a mean follow-up period of 17.5 ± 3.8 years (P<0.001). Regarding the Minimal clinically important differences (MCID), 38 cases (70.4%) showed an improvement in the Lysholm score. The cumulative clinical survival rate was 87.0%. Objective evaluations evaluated in 32 cases with a minimum of 15 years of radiographic data revealed significant progression of joint space narrowing, osteoarthritis, and cartilage degeneration at the final follow-up, with 11 (34.4%) out of 32 cases exhibiting allograft tears involving ˃50% of the allograft. Patients with osteoarthritis progression exhibited more meniscal allograft tears and extrusion on the last follow-up MRI scan than those without progression. ConclusionNotable progression in joint space narrowing, osteoarthritis, and cartilage degeneration were observed in objective assessment. The progression of osteoarthritis might be associated with allograft tears and extrusion. In clinical evaluations, favorable long-term clinical outcomes were consistently demonstrated after MAT using the bone fixation technique. Level of EvidenceLevel Ⅳ, therapeutic case series.

Prospective Assessment of Outcomes After Femoral Condyle Osteochondral Allograft Transplantation With Concurrent Meniscus Allograft Transplantation.

Osteochondral allograft transplantation (OCAT) and meniscus allograft transplantation (MAT) have each become more commonly implemented for the treatment of young to middle-aged patients with complex knee pathology. Evidence regarding tibiofemoral OCAT in the setting of concurrent MAT is limited. The purpose of this study was to characterize outcomes for femoral condyle OCAT with concurrent MAT (OCAT+MAT) in the ipsilateral compartment of patients after evidence-based shifts in practice. It was hypothesized that OCAT+MAT would be associated with successful outcomes characterized by statistically significant and clinically meaningful improvements in patient-reported outcome measures (PROMs) of knee pain and function in >80% of patients for at least 2 years after transplantation. Case series; Level of evidence, 4. With institutional review board approval and documented informed consent, patients who underwent primary OCAT+MAT between 2016 and 2020 and enrolled in a lifelong registry for prospective collection of outcomes after OCAT were included. Patients with minimum 2-year follow-up data regarding complications, failures, adherence, and PROMs were analyzed. Patients who required OCAT and/or MAT revision or conversion to arthroplasty were defined as experiencing treatment failures. A total of 23 consecutive patients (mean age, 37.1 years; mean body mass index, 28 kg/m2; 14 men) met the inclusion criteria, with a mean follow-up of 51 months (range, 24-86 months). The initial treatment success rate was 78% based on 5 initial treatment failures, and the overall success rate was 83% based on a successful revision OCAT. All failures occurred in the medial compartment. Older patient age (42.2 vs 32.1 years; P = .046) and nonadherence to postoperative restriction and rehabilitation protocols (P = .033; odds ratio, 14) were significant risk factors for treatment failure. All measured PROMs achieved significant improvements (P < .001) and minimum clinically important differences at a minimum of 2 years postoperatively. OCAT+MAT was associated with successful short- to mid-term outcomes in 83% of cases. Evidence-based shifts in practice were implemented before the enrollment of this patient cohort. Older patients and those who were not adherent to postoperative restriction and rehabilitation protocols had a significantly higher risk for treatment failure and subsequent conversion to arthroplasty.

Differences in Graft Tear Configurations in Medial and Lateral Meniscal Allograft Transplantation: Objective Evaluations Using Magnetic Resonance Imaging

Background: Few studies have compared the characteristics of meniscal allograft tears between medial and lateral meniscal allograft transplantation (MAT) using bone fixation. Purpose: To investigate the prevalence, location, and patterns of allograft tears after MAT with the bone fixation technique and compare tear patterns between medial and lateral compartments according to the time elapsed after surgery. Study Design: Cohort study; Level of evidence, 3. Methods: The charts of consecutive patients who underwent primary medial or lateral MAT between December 1996 and June 2019 were retrospectively reviewed. The location, pattern, and postoperative periods during which allograft tears occurred were evaluated by reviewing all series of follow-up magnetic resonance imaging (MRI) scans, which were performed at 6 weeks, 3 months, 6 months, and 1 year postoperatively and every 2 years thereafter with the patient's agreement. Postoperative periods for allograft tears were defined as the time between surgery and the follow-up MRI scan in which the meniscal tear was first confirmed. Allograft tears were compared between the medial and lateral MAT groups. Results: A total of 327 consecutive patients who underwent MAT (55 medial, 272 lateral) with a minimum 2-year follow-up were retrospectively reviewed. The incidences of allograft tears after medial and lateral MATs were 32.7% and 30.9%, respectively. The mean times for tears were 80.1 ± 81.1 months and 48.9 ± 46.3 months in the medial and lateral MAT groups, respectively (P = .130). In both the medial and lateral MAT groups, allograft tears were observed mainly in the posterior horn, with complex tears being the most commonly identified tear type. In medial MATs, root tears were the second most common at 27.8%, with a significantly higher proportion than the lateral MATs (P = .014). On the other hand, in lateral MATs, meniscocapsular separation and radial tears were the second most common at 15.5% each, albeit not significantly more common than in medial MATs (P = .123 and P = .454, respectively). All root tears in medial MATs and meniscocapsular separations in lateral MATs were observed within 1 year postoperatively. Conclusion: Significant differences in allograft tear patterns were identified between the medial and lateral MAT groups. The proportion of root tears in medial MATs was higher than that in lateral MATs; conversely, the proportion of meniscocapsular separation was more common in lateral MATs. Such tear patterns, which may require surgical repair or graft resection, were observed only within 1 year of surgery. Therefore, close observation and regular follow-up in the earlier postoperative period are necessary after medial or lateral MATs.

Load Distribution After Serial Resection of the Posterior Horn of the Lateral Meniscus and Subsequent Meniscal Allograft Transplant: A Biomechanical Study

Background: Data are lacking as to when a meniscal allograft transplant (MAT) may be biomechanically superior to a partially resected lateral meniscus. Hypothesis: Lateral MAT using a bone bridge technique would restore load distribution and contact pressures in the tibiofemoral joint to levels superior to those of a partial lateral meniscectomy. Study Design: Controlled laboratory study. Methods: Eleven fresh-frozen human cadaveric knees were evaluated in 5 lateral meniscal testing conditions (native, one-third posterior horn meniscectomy, two-thirds posterior horn meniscectomy, total meniscectomy, MAT) at 3 flexion angles (0°, 30°, and 60°) under a 1600-N axial load. Pressure sensors were used to acquire contact pressure, contact area, and peak contact pressure within the tibiofemoral joint. Results: Limited (one-third and two-thirds) partial lateral posterior horn meniscectomy showed no significant increase in mean and peak contact pressures as well as no significant decrease in contact area compared with the intact state. Total meniscectomy significantly increased mean contact pressure at 0° and 30° (P = .008 and P < .001, respectively), increased peak contact pressure at 30° (P = .04), and decreased mean contact area in all flexion angles compared with the native condition (P < .01). Lateral MAT significantly improved mean contact pressure compared with total meniscectomy at 0° and 30° (P = .002 and P = .003, respectively) and increased contact area at 30° and 60° (P = .003 and P = .009, respectively), although contact area was still significantly smaller (24.1%) after MAT relative to the native meniscus (P = 0.015). However, allograft transplant did not result in better tibiofemoral contact biomechanics compared with limited partial meniscectomy (P > .05). Conclusion: The peripheral portion of the lateral meniscus provided the most important contribution to the distribution of contact pressure across the tibiofemoral joint in the cadaveric model. Total meniscectomy significantly increased mean and peak contact pressure in the cadaveric model and decreased contact area. Lateral MAT restored contact biomechanics close to normal but was not superior to the partially meniscectomized status. Clinical Relevance: Surgeons should attempt to preserve a peripheral rim of the posterior lateral meniscus. Meniscal allograft transplant appears to improve but not normalize mean contact pressure and contact area relative to total lateral meniscectomy.

Meniscal Allograft versus Synthetic Graft in Treatment Outcomes of Meniscus Repair: A Mini-review and Meta-analysis.

Meniscal injuries are highly correlated with osteoarthritis (OA) onset and progression. Although meniscal allograft transplantation (MAT) is a therapeutic option to restore meniscal anatomy, a shortage of donor material and the donor-derived infectious risk may be concerns in clinics. This review summarizes the literature reporting meniscus repair status in preclinical models and clinical practice using allografts or synthetic grafts. The advantages and limitations of biodegradable polymer-based meniscal scaffolds, applied in preclinical studies, are discussed. Then, the long-term treatment outcomes of patients with allografts or commercial synthetic scaffolds are compared. A total of 47 studies are included in our network meta-analysis. Compared with the meniscal allografts, the commercial synthetic products significantly improved clinical treatment outcomes in terms of the Knee Injury and Osteoarthritis Outcome Score (KOOS), Visual Analog Scale (VAS) scores, and Lysholm scores. In addition, development strategies for the next generation of novel synthetic scaffolds are proposed through optimization of structural design and fabrication, and selection of cell sources, external stimuli, and active ingredients. This review may inspire researchers and surgeons to design and fabricate clinic-orientated grafts with improved treatment outcomes.

Paper 15: Survivorship of 157 Arthroscopic Meniscal Allograft Transplants Using Bone Fixation at Mean 7 Years and Prognostic Factors Analysis

Objectives: Meniscal allograft transplantation (MAT) is an accepted and effective treatment option in the context of unsalvageable menisci, particularly in young and active patients. It has been shown to reduce pain and improve knee function in previously symptomatic patients. However, there is still limited knowledge about the long-term survival rates of allografts, the durability of clinical results, and the influence of patient-specific parameters, such as leg alignment, tibial slope, and preoperative International Cartilage Regeneration &amp; Joint Preservation Society (ICRS) grade. The purpose of this study was to determine (1) the long-term clinical success rate after MAT with bony fixation in a large, single-center cohort of consecutive patients, and (2) if patient-specific and procedural variables influence the clinical, anatomic, and subjective outcomes and risk of failure. Methods: Data on 185 consecutive knees undergoing MAT in a single institution were prospectively collected and screened for inclusion in this study. The minimum follow-up time was 2 years. Radiographic variables (International Cartilage Regeneration &amp; Joint Preservation Society [ICRS] grade and Kellgren and Lawrence grade) were assessed preoperatively and at follow-up. Subjective patient-reported outcome measures (PROMs), Lysholm score, Knee Disability and Osteoarthritis Outcome Score (KOOS) including subscores, International Knee Documentation Committee (IKDC) score, and visual analog score (VAS) were collected preoperatively and at follow-up. Clinical failure was defined as revision surgery due to graft failure or conversion to total knee arthroplasty (TKA). Anatomic failure was considered a tear covering &gt;20% of the allograft, any peripheral tear, and unstable peripheral fixation leading to dislocation of the graft. Subjective failure was defined as Lysholm score ≤65. Preoperative tibial slope and leg alignment were assessed. Survival analyses were performed utilizing the Kaplan-Meier estimate. Univariate and multivariate analyses were performed to determine risk factors for clinical and anatomic failure. Results: A total of 157 knees met inclusion criteria (Table 1). After a mean follow-up time of 7 ± 3.5 years, 127 (80.9%) knees were free of clinical, anatomic, and subjective failure. Fourteen (8.9%) knees experienced clinical failure, 26 (16.6%) knees were identified as anatomic failure, and 13 patients (8.3%) suffered from subjective failure with a reported Lysholm score of ≤65 at a mean follow-up of 7 years. Concurrent osteochondral allograft transplantation was identified as a predictor of both clinical (HR 4.55; 95% CI 1.46-14.17; p=0.009) and anatomic failure (HR 3.05; 95% CI 1.34-6.92; p=0.008). Cartilage damage of ICRS grade 3 or 4 of the index compartment conveyed an increased risk for clinical (HR 3.41; 95% CI 1.05-11.01; p=0.04) and anatomic failure (HR 3.04; 95% CI 1.31-7.11; p=0.01) (Table 2). There were no differences in outcomes between medial and lateral MAT. High-grade cartilage damage (defined as ICRS grades 3 and 4) preoperatively (HR 10.67; 95% CI 1.037-109.768; p=0.046), patients age over 25 (HR 5.44; 95% CI 0.120-246.070; p=0.384), and a body mass index &gt;30 (HR 2.24; 95% CI 0.748-6.705; p=0.149) were associated with subjective failure. Considering the entire study population, PROMs including KOOS and IKDC were significantly improved at final follow-up compared to preoperative scores across all measurements (p&lt;0.005). Conclusions: MAT showed good-to-excellent clinical results at a mean follow-up of 7 years. Low ICRS lesion grade was associated with a higher clinical and anatomic survival rate. Patients with concurrent osteochondral allograft transplantation are at higher risk of clinical and anatomic failure, but still report significantly improved PROMs. These results suggest MAT has a lasting beneficial effect both as in isolation and in complex cases with one or more concurrent procedures.

Poster 232: Clinical Outcomes of Medial Meniscus Allograft Transplantation (MAT) with or without High Tibial Osteotomy (HTO): A Case-Control Study up to 8 Years of Follow-up

Poster 232: Clinical Outcomes of Medial Meniscus Allograft Transplantation (MAT) with or without High Tibial Osteotomy (HTO): A Case-Control Study up to 8 Years of Follow-up

Paper 31: Patient Reported and Clinical Outcomes of High Tibial Osteotomy and Distal Femoral Osteotomy in High Level Athletes

Objectives: High Tibial Osteotomy (HTO) and Distal Femoral Osteotomy (DFO) have long been utilized in the treatment of symptomatic osteoarthritis as well as malalignment with instability, meniscal deficiency or chondral defects. There remains a paucity of literature on the clinical and patient reported outcomes following HTO and DFO procedures in high level athletes. The purpose of this study is to present the outcomes in high-level athletes following HTO and DFO surgery at a large academic institution. Methods: High-level athletic patients (defined as Tegner score over 5) undergoing HTO/DFO from January 2010 to August 2023 were eligible for inclusion. Patients were excluded if they were less than 18 years old, had a Tegner score below 5 prior to symptom onset or had less than 2 years of follow-up. Demographic data including sex, age at time of surgery, and body mass index (BMI) at time of surgery was obtained from the EMR. Outcomes were assessed using follow-up questionnaires that consisted of symptom resolution, patient satisfaction, Tegner Activity Scale, IKDC, KOOS, Lysholm, and return to sports. Patients with concomitant meniscus allograft transplantation, osteochondral allograft transplantation and anterior cruciate ligament reconstruction were included. Results: There were 52 patients that met inclusion criteria, with 39 (75.0%) of patients undergoing HTO and 13 (25.0%) patients undergoing DFO. The mean age at the time of surgery was 39.5 ± 11.1 years, mean follow-up was 5.6 ± 3.1 years (2.0-12.2 years). The cohort was 71.2% male with average BMI of 26.8 ±4.1 Complete symptomatic resolution was reported by 46.2% of patients. When asked about their overall physical ability after surgery, 41.2% patients said they were “much better”, with 27.5% patients saying they were “better”. The mean VAS satisfaction score at final follow-up was 73.7 and 64.7% patients would choose to undergo the operation again if given the option. There was a significant decrease in the value of VAS pain score from the patient’s pre-operative level after knee injury versus their current pain level (73.6 vs. 29.5, p&lt;0.0001). Furthermore, 3/51 (5.9%) patients eventually underwent total knee arthroplasty with an average time of 2.9 ± 0.2 years form HTO/DFO procedure. The mean Tegner score before injury was 6.4, before surgery was 2.7 and a significant increase to 4.3 (p&lt;0.0001) after the procedure at follow up. Following surgery 82.7% of patients met the threshold for patient acceptable symptom state (PASS) for IKDC. 44 percent returned to sports after surgery and only 12 (25.0%) were able to return to sport to the same level from before their injury. The average time to return to sport was 47.3 ±27.0 weeks. There was a significant difference between male and female patients undergoing HTO/DFO procedures with respect to IKDC (p=0.027), KOOS symptom (p=0.048), KOOS activities of daily living (p=0.050), KOOS pain (p=0.050), KOOS QoL (p=0.039) and KOOS sports (p=0.016). Additionally, there was no significant difference in any of the clinical or patient reported outcomes studied between patients who underwent HTO/DFO procedures for degenerative joint disease versus instability aside from IKDC (72.8 vs. 61.1, p=0.046) and KOOS ADL (92.1 vs. 81.0, p=0.037). Conclusions: In high level-athletes, HTO and DFO procedures lead to high satisfaction rates and significant increases in Tegner scores following surgery compared to their symptomatic baseline, with low conversion rates to total knee arthroplasty at mid-term follow up, with male patients having better outcomes. The majority of patients did not return to sport following these procedures and even fewer were able to return to sport at their pre-injury activity level. Surgeons can use the findings from this study to educate high-level athletes that HTO/DFO procedures provide reliable improvements in clinical and patient reported outcomes with high patient satisfaction but may not allow them to return to sport at their pre-injury level.

Clinical and Radiological Outcomes of Medial Meniscal Allograft Transplantation Combined With Realignment Surgery.

The outcomes of medial meniscal allograft transplantation (MMAT) combined with high tibial osteotomy (HTO) compared with isolated MMAT remain unclear. To compare the clinical and radiological results of MMAT combined with HTO and isolated MMAT. Cohort study; Level of evidence, 3. This retrospective study included 42 consecutive patients, who were divided into group M (isolated MMAT; n = 22) and group H (MMAT combined with HTO with a varus angle >3°; n = 20). Group differences in subjective knee scores, isokinetic muscle strength test, and radiological outcomes (Kellgren-Lawrence grade, mechanical axis, graft extrusion, graft status, and articular cartilage loss) were compared. The mean follow-up period was 29.2 ± 4.9 months and 27.4 ± 5.3 months for groups M and H, respectively. The Lysholm score improved from 55.4 ± 9.5 to 81.3 ± 9.7 and from 52.6 ± 8.9 to 84.2 ± 10.2 in groups M and H, respectively (both P < .001). The International Knee Documentation Committee subjective score improved from 51.4 ± 10.3 to 79.6 ± 9.4 and from 49.3 ± 11.4 to 81.4 ± 8.3 in groups M and H, respectively (both P < .001). Both groups showed no significant differences in subjective knee scores and isokinetic extensor strength at the final follow-up. The rate of preoperative and postoperative high International Cartilage Regeneration & Joint Preservation Society grade (≥3) did not differ between the 2 groups. Group M showed greater coronal graft extrusion than did group H (3.3 ± 0.7 mm vs 2.7 ± 0.8 mm; P = .014); the rate of pathologic graft extrusion (≥3 mm) was not higher in group M (40.9%) than in group H (20%) with the number of patients available (P = .143). Both groups showed no significant difference in the graft status. Graft tears were observed in 2 patients (9%) in group M and 1 patient (5%) in group H (P = .607). Clinical scores significantly improved after isolated MMAT and MMAT combined with HTO compared with preoperative values, and their short-term outcomes were similar. Postoperative graft extrusion was greater in patients who underwent isolated MMAT, implying that active correction of varus alignment during MMAT may help in intra-articular biomechanics.

Long-Term Clinical and Radiographic Outcomes of Meniscus Allograft Transplant.

To reduce pain, improve function and possibly mitigate the risk for development of osteoarthritis in patients with functionally deficient meniscus pathology, meniscal allograft transplantation (MAT) can be used to restore native joint biomechanics and increase knee joint longevity. This review explores the senior author's preferred bridge-in-slot technique and recently published long-term clinical and radiographic outcomes following MAT. Recent literature demonstrates MAT to be a safe and largely successful procedure for patients with functional meniscus deficiency. A majority of patients reach established minimal clinically important difference (MCID) values. Graft survivorship is approximately 80% at 10years, significantly delaying and in some cases, preventing the need for future joint reconstruction procedures in these young patients. Return to sport rates are over 70%, revealing meniscal allografts can withstand high impact activities. Cartilage damage at the time of MAT increases the risk for graft and clinical failure, though this may be mitigated with a concomitant cartilage restoration procedure. Meniscal allograft transplantation can provide a durable and effective long-term solution to meniscal deficiency in symptomatic patients who wish to decrease the risk of symptomatic progression and possibly further osteoarthritis and continue activities of daily life and sports with less pain and more function. By restoring more normal joint biomechanics, MAT can mitigate the potential need for future knee arthroplasty in this young active patient population.

Discoid meniscus: Treatment considerations and updates.

A discoid meniscus is a morphological abnormality wherein the meniscus loses its normal 'C' shape. Although most patients are asymptomatic, patients might still present with symptoms such as locking, pain, swelling, or giving way. Magnetic resonance imaging is usually needed for confirmation of diagnosis. Based on a constellation of factors, including clinical and radiological, different approaches are chosen for the management of discoid meniscus. The purpose of this review is to outline the treatment of discoid meniscus, starting from conservative approach, to the different surgical options for this condition. The PubMed and Google Scholar databases were used for this review. Studies discussing the treatment of discoid meniscus from 2018 to 2023 were searched. Initially there were 369 studies retrieved, and after removal of studies using the exclusion criteria, 26 studies were included in this review. Factors such as stability, presence of tear, and morphology can help with surgical planning. Many approaches have been used to treat discoid meniscus, where the choice is tailored for each patient individually. Postoperatively, factors that may positively impact patient outcomes include male sex, body mass index < 18.5, age at symptom onset < 25 years, and duration of symptoms < 24 months. The conventional approach is partial meniscectomy with or without repair; however, recently, there has been an increased emphasis on discoid-preserving techniques such as meniscoplasty, meniscopexy, and meniscal allograft transplantation.

10-Year Survival and Clinical Improvement of Meniscal Allograft Transplantation in Early to Moderate Knee Osteoarthritis

Background: Meniscal allograft transplantation (MAT) is a viable option for patients experiencing unicompartmental knee pain after total or subtotal meniscectomy. Nonetheless, caution is recommended when suggesting this procedure in the presence of knee osteoarthritis (OA) because of the higher risk of poor survival and outcomes. Purpose/Hypothesis: The purpose was to document the long-term survival of MAT performed as a salvage procedure in patients with knee OA. The hypothesis was that MAT would significantly reduce pain and increase the function of the affected joint at a long-term follow-up compared with the preoperative condition, with a low number of failures and knee replacement surgeries. Study Design: Case series; Level of evidence, 4. Methods: A total of 47 patients (37 men and 10 women) with symptomatic knee OA (Kellgren-Lawrence grades 2 or 3) treated with MAT were evaluated at baseline, 5 years, and a minimum 10-year final follow-up (11.1 ± 1 years) using the Lysholm score, the visual analog scale for pain, the Knee injury and Osteoarthritis Outcome Score subscales, and the Tegner score. A total of 44 patients had undergone previous surgeries. Patient satisfaction, revision surgeries, and failures were also recorded. Results: A statistically significant improvement was observed in all clinical scores from the baseline assessment to the final follow-up. The Lysholm score improved significantly from 46.4 ± 17.2 at the preoperative assessment to 77.7 ± 20.4 at the intermediate follow-up (P < .001), with a significant decrease at the final follow-up (71 ± 23.3; P = .018). A similar trend was reported for the visual analog scale scale for pain, Knee injury and Osteoarthritis Outcome Score, and Tegner score, with no complete recovery to the previous sports activity level. A total of 33 patients required concurrent procedures, such as anterior cruciate ligament reconstructions, osteotomies, and cartilage procedures. Five patients underwent reoperation and were considered surgical failures, while 15 patients presented a clinical condition of <65 of the Lysholm score and were considered clinical failures. Among these, 4 patients were considered both surgical and clinical failures. Conclusion: MAT surgery has proven to be a valid option for improving pain and function even in OA joints (Kellgren-Lawrence grades 2 or 3), yielding satisfactory results despite a worsening clinical outcome in the long-term follow-up. Therefore, based on the data from this study, orthopaedic surgeons may consider recommending MAT as a salvage procedure even in knees affected by early to moderate OA, while advising patients that the need for combined interventions could potentially reduce graft survival.

Meniscus Tears in Elite Athletes: Treatment Considerations, Clinical Outcomes, and Return to Play.

Management of meniscal injuries in the elite athlete is a difficult problem secondary to the high demands of athletic competition, the need for a timely return to sport, and the desire to maximize performance over time. The purpose of this review is to provide an up-to-date summary on the current literature and trends regarding the management of meniscus injuries with a special consideration for elite athletes. Historically, partial meniscectomy has been the primary treatment option for meniscus injuries. However, in recent years there has been an increased emphasis on meniscus preservation due to the increased risk of cartilage degeneration over time. Moreover, while partial meniscectomy still provides a quicker return to sport (RTS), recent literature has demonstrated similar rates of RTS and return to pre-injury levels between partial meniscectomy and meniscus repair. In the setting of symptomatic meniscal deficiency, meniscus allograft transplantation has become an increasingly utilized salvage procedure with promising yet variable outcomes on the ability to withstand elite competition. Currently, there is no uniform approach to treating meniscal injuries in elite athletes. Therefore, an individualized approach is required with consideration of the meniscus tear type, location, concomitant injuries, athlete expectations, rehabilitation timeline, and desire to prevent or delay knee osteoarthritis. In athletes with anatomically repairable tears, meniscus repair should be performed given the ability to restore native anatomy, provide high rates of RTS, and mitigate long-term chondral damage. However, partial meniscectomy can be indicated for unrepairable tears.

Meniscal Transplant surgery or Optimised Rehabilitation full randomised trial (MeTeOR2): a study protocol

IntroductionPain and disability after meniscectomy can be a substantial lifelong problem. There are few treatment options, especially for young people. Non-surgical management (rehabilitation) is an option but increasingly surgeons are...

Meniscus Allograft Transplantation in Conjunction With Arthroscopic Biologic Knee Restoration Delays Arthroplasty in Patients Older Than 50 Years

The purpose of this study is to evaluate the utility of meniscus allografts in combination with other procedures to delay knee arthroplasty in patients older than 50 years of age previously advised joint arthroplasty. One hundred eight meniscus allograft transplants (MATs) using the arthroscopic three tunnel technique between 1997 and 2019 in patients over 50 years of age were retrospectively reviewed with two-year minimum follow-up period. Inclusion criteria were patients recommended knee arthroplasty with pain and preservation of some joint space by standing flexion x-rays. Exclusion criteria were lack of joint space, failure to comply with rehabilitation protocol or complete research questionnaires. International Knee Documentation Committee (IKDC) composite and isolated pain scale were evaluated longitudinally. Time from MAT to arthroplasty was measured with failure defined as allograft excision or revision, progression to arthroplasty, or same or increased pain. Eighty-six of 108 (79.6%) patients met eligibility criteria. Over the follow-up mean 8.55 (range of 0.68 to 25.2) years, 42 of 87 (48.2%) grafts progressed to arthroplasty with mean time of 8.64 (median 8.05) years. Concomitant procedures did not have significant impact on survival; however, survival medians were higher among paste graft and chondroplasty and lower among osteotomy groups. At the time of reporting, 41 of 84 (48.8%) patients had intact meniscus transplants, demonstrating significant improvements (p<0.001) in pain and function as assessed by IKDC. These improvements were sustained ten years post-operatively, correlated to a mean of 65.8 years of age. At least 50% of patients achieved Minimal Clinically Important Difference (MCID) through 10 years post-operatively. Meniscus allografts in combination with other arthroscopic interventions delay knee arthroplasty and improve knee symptoms of pain and function in a population of knee arthroplasty candidates over 50 years of age. Influences of concomitant procedures cannot be defined.

Meniscal allograft transplantation (MAT) combined with revision ACL reconstruction and lateral extra-articular tenodesis results in significantly improved outcomes, but patient-reported knee function is inferior compared to an isolated MAT.

Meniscal allograft transplantation (MAT) is a valuable option for postmeniscectomy syndrome in young and active patients, which can successfully improve symptoms, function and quality of life. This study aimed to report outcomes and complications in patients treated with isolated MAT or MAT combined with revision anterior cruciate ligament reconstruction (ACLR) and lateral extra-articular tenodesis (LET). In total, 18 patients who were treated with MAT using a soft tissue fixation technique were retrospectively analysed. Patients were allocated into two groups, the isolated MAT group and the MAT plus revision ACLR + LET group (MAT+ group). Both groups were assessed using the following Patient-Reported Outcome Measures (PROMs): Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC), Tegner Activity Scale, Lysholm score, EuroQol 5-Dimension 5-level (EQ-5D-5L) questionnaire and a patient acceptable symptom state (PASS) statement. The mean follow-up was 3.2 years and the mean age of patients was 29 (±7.6) years. Ten patients were treated with isolated MAT and eight patients were treated with MAT combined with revision ACLR and LET. No complications and no reoperations were reported. In both groups, all PROMs significantly improved postoperatively (p < 0.05), except for the Tegner score in the MAT+ group, which did not reach statistical significance (not significant [n.s.]). No significant difference was found postoperatively in PROMs between the MAT and the MAT+ group; however, differences in the KOOS Symptoms, Sports and Quality-of-life subscales reached the minimal clinically important threshold. Mean values were: IKDC 61.2 (±13.9) versus 64.7 (±23.2), KOOS Total 72.8 (±14.9) versus 68.0 (±16.7), Lysholm score 83.2 (±11) versus 84.2 (±8.7) and EQ-5D-5L 71.8 (±14.9) versus 72.2 (±22.4). Median values for the Tegner Activity Scale were 4 versus 3. PASS statement was negative in 37.5% of the MAT+ group in comparison to 20% of the MAT group (n.s.). In terms of patient-reported outcomes, MAT is an effective and safe procedure, even when combined with revision ACLR + LET. Compared to the preoperative assessment, a significant improvement of the postoperative PROMs can be expected either when MAT is performed isolated or in combination with ACLR + LET. However, clinically important differences between the two groups can be noted in favour of the isolated MAT procedure, especially regarding symptoms and sporting activity. Level III.