Short-Term but Not Long-Term Knee Symptoms and Functional Improvements of Tissue Engineering Strategy for Meniscus Defects: A Systematic Review of Clinical Studies.

PURPOSE: To investigate the up-to-date clinical outcomes of tissue-engineered meniscus implants for meniscus defects. METHODS: A search was performed by 3 independent reviewers on PubMed, MEDLINE, EMBASE, and Cochrane from 2016 to June 18, 2023, with the term "meniscus" with all the following terms: "scaffolds," "constructs," "implant," and "tissue engineering." Inclusion criteria included "Clinical trials" and "English language articles" that involved isolated meniscus tissue engineering strategies for meniscus injuries. Only Level I to IV clinical studies were considered. The modified Coleman Methodology score was used for quality analysis of included clinical trials. The Methodological Index for Non-Randomized Studies was employed for analysis of the risk of study bias and methodological quality. RESULTS: The search identified 2,280 articles, and finally 19 original clinical trials meeting the inclusion criteria were included. Three types of tissue-engineered meniscus implants (CMI-Menaflex, Actifit, and NUsurface) have been clinically evaluated for meniscus reconstruction. Lack of standardized outcome measures and imaging protocols limits comparison between studies. CONCLUSIONS: Tissue-engineered meniscus implants can provide short-term knee symptom and function improvements, but no implants have been shown to propose significant long-term benefits for meniscus defects. LEVEL OF EVIDENCE: Level IV, systematic review of Level I to IV studies.

Single- or two-stage revision after failed ACL reconstruction: No differences in re-revision rates and clinical outcomes.

PURPOSE: The surgeons' choice of a single-stage or a two-stage procedure in revision anterior cruciate ligament reconstruction (ACLr) is based on the possibility of reuse of the tibia and femoral bone tunnels after primary ACLr. The purpose of this study was to compare failure rates and clinical outcomes following single-stage and two-stage ACL revisions in a cohort of patients from The Danish Knee Ligament Reconstruction Registry. METHODS: Patients identified from 2005 to 2022 with ACL revision and met the following criteria: minimum 2-year follow-up, isolated ACL revision and registered single- or two-stage ACL revision. The primary outcome was ACL re-revision rate. Secondary outcomes were arthrometer sagittal knee laxity (side-to-side difference) and pivot shift (rotational stability difference) evaluated at 1-year follow up. RESULTS: One thousand five hundred seventy-four ACL revisions were included in the study (1331 = single-stage and 243 = two stage). Baseline characteristics showed no difference in relation to age, gender, knee laxity, pivot shift, meniscus injury, cartilage damage or injury mechanism between the two groups. Significant differences were found in relation to the type of graft. No statistical difference in 2-years revision rates between single-stage group 2.79 (95% CI 2.03-3.84) and two-stage group 2.93 (95% CI 1.41-6.05) was found. No significant difference was seen in knee laxity and pivot shift between stage-groups at 1-year follow up. Both groups demonstrated significant improvements in knee stability from baseline to 1-year follow-up. CONCLUSION: The present study found that ACL revision outcomes were similar in terms of rerevision rates and knee laxity for patients managed with a single- or a two-stage surgical strategy. LEVEL OF EVIDENCE: Level III.

Influence of Graft Type and Meniscal Involvement on Short-Term Outcomes Following Anterior Cruciate Ligament Reconstruction.

CONTEXT: The purpose of this study was to compare short-term clinical outcomes between meniscus procedures performed with anterior cruciate ligament reconstruction (ACLR), ACLR (ACLR-only), ACLR with meniscectomy/resection (ACLR-resect), and ACLR with meniscal repair (ACLR-repair) for bone patellar tendon bone grafts (BPTB) and hamstring tendon grafts, separately. DESIGN: This was a cross-sectional study conducted in a controlled laboratory setting as part of a large point-of-care collaborative research program. METHODS: This study included 314 participants (168 females; mean [SD]: age, 19.7 [4.8]) with primary unilateral ACLR with a BPTB or hamstring tendon. Patients were divided into 3 groups depending on meniscal procedure (ACLR-only, ACLR-resect, and ACLR-repair). Postsurgical testing included: isokinetic assessment of knee extension and flexion, single-leg hop tests, and patient-reported outcomes. Multivariate analysis of covariance compared differences between meniscal procedures on the battery of tests, and for each statistically significant variable an analysis of covariance assessed the effect of meniscal procedure within each graft type. Chi-square analysis assessed the influence of meniscal procedure on tests' pass rates defined as 90% of limb symmetry index. RESULTS: BPTB: ACLR-only had greater hamstring strength than ACLR-resect (P = .05) and ACLR-repair (P = .005). ACLR-only had the highest proportion of participants to pass the hamstring strength test (P = .02). Hamstring tendon: ACLR-only (P = .03) and ACLR-resect (P = .003) had higher International Knee Documentation Committee scale scores than ACLR-repair. There was a significant difference in the proportion of participants who scored >90% limb symmetry index on the timed hop test (P = .05). CONCLUSIONS: The influence of meniscal repair on clinical outcomes is dependent on the graft choice. Following an ACLR with BPTB and a meniscal procedure, hamstring function should be more closely monitored for optimal short-term recovery.

Perioperative outcomes in isolated versus multiligamentous anterior cruciate ligament reconstruction: a retrospective cohort analysis.

PURPOSE: The outcomes of anterior cruciate ligament reconstruction in the setting of multiligamentous knee injury (M-ACLR) have not been well characterized compared to isolated ACLR (I-ACLR). This study aims to characterize and compare short-term outcomes between I-ACLR and M-ACLR. METHODS: This is a retrospective cohort analysis of the American College of Surgeons National Surgical Quality Improvement Program database from 2005 to 2017. Current Procedural Terminology codes were used to identify and compare elective I- and M-ACLR patients, excluding patients undergoing concomitant meniscal or chondral procedures. Patient demographics and outcomes after I- and M-ACLR were compared using bivariate analysis. Multiple logistic regression analyzed if multiligamentous ACLR was an independent risk factor for adverse outcomes. RESULTS: There was a total of 13,131 ACLR cases, of which 341 were multiligamentous cases. The modified fragility index-5 was higher in multiligamentous ACLR (p < 0.001). Multiligamentous ACLR had worse perioperative outcomes, with higher rate of all complications (3.8%, p = 0.013), operative time > 1.5 h (p < 0.001), length of stay (LOS) ≥ 1 day (p < 0.001), wound complication (2.1%, p = 0.001), and intra- or post-op transfusions (p < 0.001). In multiple logistic regression, multiligamentous ACLR was an independent risk factor for LOS ≥ 1 (odds ratio [OR] 5.8), and intra-/post-op transfusion (OR 215.1) and wound complications (OR 2.4). M-ACLR was not an independent risk factor for any complication, reoperation at 30 days, readmission, urinary tract infection (UTI), or venous thromboembolism (VTE). CONCLUSION: M-ACLR generally had worse outcomes than I-ACLR, including longer LOS, need for perioperative transfusions, and wound complications.

Are Neighborhood Conditions Associated With Surgical Delays and Meniscus Tears in Children and Adolescents Undergoing ACL Reconstruction?

BACKGROUND: Markers of a patient's social determinants of health, including healthcare insurance and median household income based on ZIP Code, have been associated with the interval between injury and ACL reconstruction (ACLR) as well as the presence of concomitant meniscus tears in children and adolescents. However, the aforementioned surrogate indicators of a patient's social determinants of health may not reflect all socioeconomic and healthcare resources affecting the care of ACL injuries in children and adolescents. The use of multivariate indices such as the Child Opportunity Index (COI) may help to better identify patients at risk for increased risk for delay between ACL injury and surgery, as well as the incidence of meniscus tears at the time of surgery. The COI is a summative measure of 29 indicators that reflect neighborhood opportunities across three domains: education, health and environment, and social and economic factors. COI scores range from 0 to 100 (100 being the highest possible score), as well as five categorical scores (very low, low, moderate, high, and very high) based on quintile rankings. QUESTIONS/PURPOSES: To investigate the relationship between neighborhood conditions and the treatment of ACL injuries in children and adolescents via the COI, we asked: (1) Is a lower COI score associated with a longer delay between ACL injury and surgery? (2) Does a higher proportion of patients with lower COI scores have meniscus tears at the time of ACLR? METHODS: In this retrospective, comparative study, we considered data from 565 patients, 18 years or younger, who underwent primary ACLR at an urban, tertiary children's hospital between 2011 and 2021. Of these patients, 5% (31 of 565) did not have a clearly documented date of injury, 2% (11 of 565) underwent revision reconstructions, and 1% (5 of 565) underwent intentionally delayed or staged procedures. Because we specifically sought to compare patients who had low or very low COI scores (lowest two quintiles) with those who had high or very high scores (highest two quintiles), we excluded 18% (103 of 565) of patients with moderate scores. Ultimately, 73% (415 of 565) of patients with COI scores in either the top or bottom two quintiles were included. Patient addresses at the time of surgery were used to determine the COI score. There were no differences between the groups in terms of gender. However, patients with high or very high COI scores had a lower median (IQR) age (15 years [2.6] versus 17 years [1.8]; p < 0.001) and BMI (23 kg/m 2 [6.1] versus 25 kg/m 2 [8.8]; p < 0.001), were more commonly privately insured (62% [117 of 188] versus 22% [51 of 227]; p < 0.001), and had a higher proportion of patients identifying as White (67% [126 of 188] versus 6.2% [14 of 227]; p < 0.001) compared with patients with low or very low COI scores. Medical records were reviewed for demographic, preoperative, and intraoperative data. Univariate analyses focused on the relationship of the COI and interval between injury and surgery, frequency of concomitant meniscus tears, and frequency of irreparable meniscus tears treated with partial meniscectomy. Multivariable regression analyses were used to determine factors that were independently associated with delayed surgery (longer than 60 and 90 days after injury), presence of concomitant meniscal injuries, and performance of meniscectomy. Multivariable models included insurance and race or ethnicity to determine whether COI was independently associative after accounting for these variables. RESULTS: Patients with a high or very high COI score had surgery earlier than those with a low or very low COI score (median [IQR] 53 days [53] versus 97 days [104]; p < 0.001). After adjusting for insurance and race/ethnicity, we found that patients with a low or very low COI score were more likely than patients with a high or very high COI score to have surgery more than 60 days after injury (OR 2.1 [95% CI 1.1 to 4.0]; p = 0.02) or more than 90 days after injury (OR 1.8 [95% CI 1.1 to 3.4]; p = 0.04). Furthermore, patients with low or very low COI scores were more likely to have concomitant meniscus tears (OR 1.6 [95% CI 1.1 to 2.5]; p = 0.04) compared with patients with high or very high COI scores. After controlling for insurance, race/ethnicity, time to surgery, and other variables, there was no association between COI and meniscectomy (OR 1.6 [95% CI 0.9 to 2.8]; p = 0.12) or presence of a chondral injury (OR 1.7 [95% CI 0.7 to 3.9]; p = 0.20). CONCLUSION: As the COI score is independently associated with a delay between ACL injury and surgery as well as the incidence of meniscus tears at the time of surgery, this score can be useful in identifying patients and communities at risk for disparate care after ACL injury. The COI score or similar metrics can be incorporated into medical records to identify at-risk patients and dedicate appropriate resources for efficient care. Additionally, neighborhoods with a low COI score may benefit from improvements in the availability of additional and/or improved resources. Future studies should focus on the relationship between the COI score and long-term patient-reported functional outcomes after ACL injury, identification of the specific timepoints in care that lead to delayed surgery for those with lower COI scores, and the impact of community-based interventions in improving health equity in children with ACL injury. LEVEL OF EVIDENCE: Level III, therapeutic study.

Efficacy of meniscus suture absorbability on meniscus healing success rate via second-look arthroscopy after meniscal repair: a systematic review and meta-analysis.

BACKGROUND: To preserve the meniscus's function, repairing the torn meniscus has become a common understanding. After which, the search for the ideal suture material is continuous. However, it is still controversial about the efficacy of suture absorbability on meniscus healing. METHODS: This review is designed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. INCLUSION CRITERIA: (1) Studies on meniscus repair; (2) Second-look arthroscopy was performed; (3) The meniscus was repaired by absorbable and non-absorbable sutures; (4) The healing condition of repaired meniscus via second-look arthroscopy was described. EXCLUSION CRITERIA: (1) Animal studies, cadaveric studies, or in vitro research; (2) Meniscus transplantation; (3) Open meniscus repair; (4) Reviews, meta-analysis, case reports, letters, and comments; (5) non-English studies. MEDLINE, Embase, and Cochrane Database were searched up to October 2022. Risk of bias and methodology quality of included literature were assessed according to ROBINS-I and the modified Coleman Methodological Scale (MCMS). Descriptive analysis was performed, and meta-analysis was completed by RevMan5.4.1. RESULTS: Four studies were included in the systematic review. Among them, three studies were brought into the meta-analysis, including 1 cohort study and 2 case series studies about 130 patients with meniscal tears combined with anterior cruciate ligament injury. Forty-two cases were repaired by absorbable sutures, and 88 were repaired by non-absorbable sutures. Using the fixed effect model, there was a statistical difference in the healing success rate between the absorbable and the non-absorbable groups [RR1.20, 95%CI (1.03, 1.40)]. CONCLUSION: In early and limited studies, insufficient evidence supports that non-absorbable sutures in meniscus repair surgery could improve meniscal healing success rate under second-look arthroscopy compared with absorbable sutures. In contrast, available data suggest that absorbable sutures have an advantage in meniscal healing. TRIAL REGISTRATION: The review was registered in the PROSPERO System Review International Pre-Registration System (Registration number CRD42021283739).

Bone Marrow-Derived Fibrin Clots Stimulate Healing of a Knee Meniscal Defect in a Rabbit Model.

PURPOSE: To determine the in vivo effectiveness of bone marrow aspirate-derived (BMA) fibrin clots for avascular meniscal defect healing in a rabbit model. METHODS: In 42 Japanese white rabbits, a 2.0-mm cylindrical defect was introduced into the avascular zone of the anterior part of the medial meniscus in the bilateral knees. The rabbits were grouped according to implantation of a BMA fibrin clot (BMA group) or a peripheral blood (PB)-derived clot (PB group) into the defect and nonimplantation (control group). Macroscopic and histological assessments were performed using a scoring system at 4 and 12 weeks after surgery. At 12 weeks after surgery, compressive stress was analyzed biomechanically. RESULTS: The meniscal score in the BMA group (12.1) was greater than that in the PB group (5.5; P = .031) and control group (4.4; P = .013) at 4 weeks. The meniscal score in the BMA group (13.1) was greater than that in the control group (6.4; BMA = 13.1; P = .0046) at 12 weeks. In the biomechanical analysis, the BMA group demonstrated significantly higher compressive strength than the PB group (6.6 MPa) (BMA = 15.4 MPa; P = .0201) and control group (3.6 MPa; BMA = 15.4 MPa; P = .007). CONCLUSIONS: Implantation of BMA fibrin clots into the meniscal defect of the avascular zone in a rabbit model improved the meniscal score at 4 weeks and strengthened the reparative meniscal tissue at 12 weeks compared with the implantation of PB fibrin clots. CLINICAL RELEVANCE: Healing in the avascular zone of the meniscus can be problematic. Approaches to improving this healing response have had variable results. This study provides additional information that may help improve the outcomes in patients with these injuries.

Editorial Commentary: Meniscal Extrusion.

With the improved recognition of meniscal root tears over the past decade, it has become clear that root repairs are necessary in most patients indicated for a repair to prevent the further progression of osteoarthritis. Root repairs are cost beneficial to and prevent the early need for a total knee arthroplasty. As further postoperative follow-up occurs for root repairs, we have found that most patients have significantly improved patient-reported outcomes, while it is still clear that further clinical outcome study as well as further refinement of surgical technique is necessary. The next thing that we have to investigate is how to prevent recurrent meniscal extrusion after a root repair. Nonanatomic repair significantly alters tibiofemoral biomechanics and results in notably increased meniscal extrusion. In contrast, biomechanical studies show anatomic repair of the meniscus attachment within 1 cm of the meniscus attachment site restores joint loading close to normal.

Combined Meniscal Allograft Transplantation and Anterior Cruciate Ligament Reconstruction Show Good 2- to 14-Year Outcomes: A Systematic Review.

PURPOSE: To evaluate the clinical outcomes of anterior cruciate ligament reconstruction (ACLR) with meniscal allograft transplantation (MAT) through a systematic review of current available evidence. METHODS: A systematic database search of PubMed, Embase, Web of Science, and CINAHL was performed from inception up to December 7, 2021, in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses. Follow-up studies (inception cohort studies/nonrandomized controlled trials/retrospective cohort studies) and case series that had more than 10 people published in English and involved patients who underwent a combination of ACLR and MAT were included. The quality of these studies was appraised using the Cochrane Risk Of Bias In Non-randomized Studies of Interventions tool. Systematic review of International Knee Documentation Committee (IKDC), Lysholm, and Tegner activity scores were conducted. RESULTS: Seven studies involving 363 patients were included. The average mean follow-up time was 4.08 years, ranging from 1.75 to 14 years. All studies used the Lysholm Knee Scoring system to report clinical outcomes, whereas 2 studies and 4 studies used the IKDC Questionnaire and Tegner activity scale respectively to measure clinical outcomes postoperatively. Comparing postoperative with preoperative scores, we found an improvement above the minimal clinically important difference for the Lysholm (mean difference [MD] range 16.00-26.10) and Tegner activity scores (MD range 1.50-1.90). All but one study reported an increase above the minimal clinically important difference for IKDC scores postoperatively (MD range 5.60-23.00). CONCLUSIONS: Combined MAT and ACLR have good 2- to 14-year clinical outcomes postoperatively and is an optimal procedure for patients with concurrent ACL injuries with irreparable meniscus injuries. LEVEL OF EVIDENCE: IV, systematic review and/or meta-analysis of studies with Levels I to IV.

Survival of anterior cruciate ligament reconstructions in active-duty military populations.

PURPOSE: Anterior cruciate ligament tears and anterior cruciate ligament reconstruction (ACLR) are common in young athletes. The modifiable and non-modifiable factors contributing to ACLR failure and reoperation are incompletely understood. The purpose of this study was to determine ACLR failure rates in a physically high-demand population and identify the patient-specific risk factors, including prolonged time between diagnosis and surgical correction, that portend failure. METHODS: A consecutive series of military service members with ACLR with and without concomitant procedures (meniscus [M] and/or cartilage [C]) done at military facilities between 2008 and 2011 was completed via the Military Health System Data Repository. This was a consecutive series of patients without a history of knee surgery for two years prior to the primary ACLR. Kaplan-Meier survival curves were estimated and evaluated with Wilcoxon test. Cox proportional hazard models calculated hazard ratios (HR) with 95% confidence intervals (95% CI) to identify demographic and surgical factors that influenced ACLR failure. RESULTS: Of the 2735 primary ACLRs included in the study, 484/2,735 (18%) experienced ACLR failure within four years, including (261/2,735) (10%) undergoing revision ACLR and (224/2,735) (8%) due to medical separation. The factors that increased failure include Army Service (HR 2.19, 95% CI 1.67, 2.87), > 180 days from injury to ACLR (HR 1.550, 95% CI 1.157, 2.076), tobacco use (HR 1.429 95% CI 1.174, 1.738), and younger patient age (HR 1.024, 95% CI 1.004, 1.044). CONCLUSION: The overall clinical failure rate of service members with ACLR is 17.7% with minimum four-year follow-up, where more patients are likely to fail due to revision surgery than medical separation. The cumulative probability of survival at 4 years was 78.5%. Smoking cessation and treating ACLR patients promptly are modifiable risk factors impacting either graft failure or medical separation. LEVEL OF EVIDENCE: Level III.

Functional performance tests, clinical measurements, and patient-reported outcome measures do not correlate as outcomes 1 year after anterior cruciate ligament reconstruction.

PURPOSE: The results after anterior cruciate ligament reconstruction (ACLR) are evaluated by laxity measures, functional tests, and patients' perception by patient-reported outcome measures (PROMs). It is not known, if one of these evaluation instruments is representative or if outcome scores from all must be reported to obtain a full evaluation of the condition. The aim was to study the correlations between these three types of outcomes 1 year after primary ACLR. METHOD: All adult patients (range 18-45 years) who had an ACLR between 1.1.2019 and 31.12.2021 were offered 1-year follow-up by an independent observer. Preoperative information about knee laxity and peroperative information about the condition of menisci and cartilage were registered. At 1-year follow-up clinical and instrumented knee stability and function assessed by four different hop tests were registered. Patients completed four PROMs (the Subjective International Knee Documentation Committee (IKDC) score, the Knee Numeric-Entity Evaluation Score (KNEES-ACL), the Knee injury and Osteoarthritis Outcome Score (KOOS) and the Lysholm score) and Tegner activity scale and answered anchor questions regarding satisfaction and willingness to repeat the operation. RESULTS: A total of 190 adults attended the 1-year follow-up and 151 had all assessments. There were only a few positive and weak correlations between performance tests and PROMS and between clinical measurements and PROMS (r = 0.00-0.38), and the majority were of negligible strength. Tegner score had in general the highest correlation (low to moderate). The highest correlation was 0.53 (moderate) between the anchor question about patient satisfaction and Lysholm/IKDC scores. There was no difference in the correlations depending on meniscal condition. CONCLUSIONS: In ACLR patients there was no clinically relevant correlation between scores obtained by PROMs, a battery of functional performance tests and instrumented laxity of the knee at 1-year follow-up. Therefore, one type of outcome cannot represent the others. This is an argument for always to include and report all three types of outcomes, and conclusions based on one type of outcome may not be sufficient. LEVEL OF EVIDENCE: II.

Graft failure within 2 years of isolated anterior cruciate ligament reconstruction is associated with increased risk of secondary meniscus tears.

PURPOSE: A debilitating complication following anterior cruciate ligament reconstruction is a secondary meniscus tear. Currently, the literature is mixed regarding the risk factors associated with the incidence of secondary meniscus tears. The aim of this study was to investigate risk factors associated with meniscus tears following an isolated primary anterior cruciate ligament reconstruction. ACL graft failure was hypothesized to be the strongest risk factor for secondary meniscal injury occurrence. METHODS: A retrospective cohort analysis was performed using the PearlDiver Database. Patients with a primary anterior cruciate ligament reconstruction were identified in the database. Patients with concomitant knee ligament injury or meniscus injury present at the time the index procedure were excluded. Patients were grouped to those who had a secondary meniscus tear within 2 years following anterior cruciate ligament reconstruction and those who did not. Univariate analysis and multivariable regression analysis was conducted to identify significant risk factors for a secondary meniscus tear. RESULTS: There were 25,622 patients meeting criteria for inclusion in this study. Within 2 years from the primary anterior cruciate ligament reconstruction, there were 1,781 patients (7.0%) that experienced a meniscus tear. Graft failure had the highest odds of having a postoperative meniscus tear within 2 years (OR: 4.1; CI 3.5-4.8; p < 0.002). Additional significant risk factors included tobacco use (OR: 2.0; CI 1.0-3.1; p < 0.001), increased Charlson Comorbidity Index (OR: 1.2; CI 1.1-1.4), male gender (OR: 1.1; CI 1.1-1.2; p < 0.001), obesity (OR: 1.1; CI 1.1-1.2; p < 0.001), delayed surgery (OR:1.1; CI 1.1-1.2; p < 0.002), and patients age 30 and older (OR: 1.0; CI 1.0-1.0; p < 0.001). CONCLUSIONS: This study found that anterior cruciate ligament graft failure is the strongest predictor of post-operative meniscus tears. Other risk factors, including tobacco use, increased CCI, male gender, obesity, delayed surgery, and age 30 and older, were established, with several being modifiable. Therefore, targeted preoperative optimization of modifiable risk factors and postoperative protocols may reduce the risk of secondary meniscus tears. LEVEL OF EVIDENCE: Level III, prognostic trial.

Health-economic evaluation of meniscus tear treatments: a systematic review.

PURPOSE: To evaluate the overall evidence of published health-economic evaluation studies on meniscus tear treatment. METHODS: Our systematic review focuses on health-economic evaluation studies of meniscus tear treatment interventions found in PubMed and Embase databases. A qualitative, descriptive approach was used to analyze the studies' results and systematically report them following PRISMA guidelines. The health-economic evaluation method for each included study was categorized following one of the four approaches: partial economic evaluation (PEE), cost-effectiveness analysis (CEA), cost-benefit analysis (CBA), or cost-utility analysis (CUA). The quality of each included study was assessed using the Consensus on Health Economic Criteria (CHEC) list. Comparisons of input variables and outcomes were made, if applicable. RESULTS: Sixteen studies were included; of these, six studies performed PEE, seven studies CUA, two studies CEA, and one study combined CBA, CUA, and CEA. The following economic comparisons were analyzed and showed the respective comparative outcomes: (1) meniscus repair was more cost-effective than arthroscopic partial meniscectomy (meniscectomy) for reparable meniscus tear; (2) non-operative treatment or physical therapy was less costly than meniscectomy for degenerative meniscus tear; (3) physical therapy with delayed meniscectomy was more cost-effective than early meniscectomy for meniscus tear with knee osteoarthritis; (4) meniscectomy without physical therapy was less costly than meniscectomy with physical therapy; (5) meniscectomy was more cost-effective than either meniscus allograft transplantation or meniscus scaffold procedure; (6) the conventional arthroscopic instrument cost was lower than laser-assisted arthroscopy in meniscectomy procedures. CONCLUSION: Results from this review suggest that meniscus repair is the most cost-effective intervention for reparable meniscus tears. Physical therapy followed by delayed meniscectomy is the most cost-effective intervention for degenerative meniscus tears. Meniscus scaffold should be avoided, especially when implemented on a large scale. LEVEL OF EVIDENCE: Systematic review of level IV studies.

Management after acute rupture of the anterior cruciate ligament (ACL). Part 1: ACL reconstruction has a protective effect on secondary meniscus and cartilage lesions.

PURPOSE: The aim of this consensus project was to validate which endogenous and exogenous factors contribute to the development of post-traumatic osteoarthritis and to what extent ACL (anterior cruciate ligament) reconstruction can prevent secondary damage to the knee joint. Based on these findings, an algorithm for the management after ACL rupture should be established. METHODS: The consensus project was initiated by the Ligament Injuries Committee of the German Knee Society (Deutsche Kniegesellschaft, DKG). A modified Delphi process was used to answer scientific questions. This process was based on key topic complexes previously formed during an initial face-to-face meeting of the steering group with the expert group. For each key topic, a comprehensive review of available literature was performed by the steering group. The results of the literature review were sent to the rating group with the option to give anonymous comments until a final consensus voting was performed. Consensus was defined a-priori as eighty percent agreement. RESULTS: Of the 17 final statements, 15 achieved consensus, and 2 have not reached consensus. Results of the consensus were summarized in an algorithm for the management after ACL rupture (infographic/Fig. 2). CONCLUSION: This consensus process has shown that the development of post-traumatic osteoarthritis is a complex multifactorial process. Exogenous (primary and secondary meniscus lesions) and endogenous factors (varus deformity) play a decisive role. Due to the complex interplay of these factors, an ACL reconstruction cannot always halt post-traumatic osteoarthritis of the knee. However, there is evidence that ACL reconstruction can prevent secondary joint damage such as meniscus lesions and that the success of meniscus repair is higher with simultaneous ACL reconstruction. Therefore, we recommend ACL reconstruction in case of a combined injury of the ACL and a meniscus lesion which is suitable for repair. LEVEL OF EVIDENCE: Level V.

Repair of a meniscus tear within 3 weeks after trauma significantly reduces the likelihood of a recurrent tear compared with later repairs.

PURPOSE: To evaluate the potential benefit of meniscus tear repair within 3 weeks after rupture compared with more than 3 weeks after rupture. METHODS: Ninety-one patients (95 menisci) underwent repair within 3 weeks after meniscus rupture [Group 1] and 15 patients (17 menisci) [Group 2] underwent repair more than 3 weeks after rupture. The posterior part of the ruptured meniscus was repaired with Contour Arrows®, using a Crossbow as the insertion instrument, whereas the middle third was repaired by inserting PDS 2.0 stitches using a Meniscus Mender® outside-in device. The patients were followed-up for a mean(SD) 8.9 years (range: 1-12 years). RESULTS: Of the 91 patients (95 menisci) in Group 1, 88 (96.7%) healed without complications. One meniscus in one patient did not heal after 11 months, requiring resection. Two other menisci in two other patients showed partially healed tears. This part was removed while preserving most of the meniscus (failure rate: 3/91 patients: 3.3%). The other 88 patients recovered without complaints and participated in sports without restraint. Four menisci in four patients experienced a second sports-related incident, resulting in a renewed tear between 12 months and 3 years. These tears were repaired successfully again. Of the 15 patients in Group 2, 12 (80.0%) healed without complications. The ruptured part of the remaining menisci in the other three patients, (20%) was removed, with all patients remaining symptom-free until the end of follow-up. Rates of treatment failure differed significantly in these two groups (3.3% vs 20.0%, p = 0.04). CONCLUSIONS: The overall failure rate was significantly lower in patients who underwent meniscus repair within 3 weeks than in those who underwent repair at 3 weeks (or more) after the trauma. Thus, early repair of meniscus tears is beneficial, and can prevent failure of meniscus repair surgery. LEVEL OF EVIDENCE: III.

Higher Grit Scores Are Associated With Earlier Increases in Knee Flexion Following Anterior Cruciate Ligament Reconstruction With Meniscus Repair in Pediatric Patients.

BACKGROUND: The Grit Scale is used to measure grit, defined by Duckworth and colleagues as the disposition to show perseverance and passion for long-term goals. It has been shown that psychological factors like motivation, coachability, and coping with adversity are correlated with faster readiness for return to sport (RTS) in patients undergoing anterior cruciate ligament reconstruction (ACLR). This study investigates the association between pediatric patients' baseline grit scores and; preoperative Patient-reported Outcomes Measurement Information System (PROMIS) Pain scores and the recovery of range of motion (ROM) after ACLR. The investigators hypothesized that higher preoperative grit scores would predict lower preoperative pain scores and earlier return of knee ROM in patients undergoing ACLR. METHODS: This is a retrospective cohort study. Pediatric patients who underwent primary ACLR were assigned the pediatric Grit Scale. Patients were subdivided by meniscal procedures due to differences in postoperative protocols. ACLR alone or with meniscectomy (ACLR ± meniscectomy) were grouped together and ACLR with meniscal repair (ACLR + meniscus repair) represented the other cohort. Patients above the 50th grit percentile were considered "high grit". Patients below the 50th percentile were considered "low grit". Baseline PROMIS pain intensity and interference were collected. ROM was compared by grit cohort using the Mann-Whitney U test with a significance threshold of P ≤ 0.05. RESULTS: A total of 58 patients undergoing ACLR were analyzed: 20 ACLR ± meniscectomy and 38 ACLR + meniscus repair. The mean age was 15.0 ± 2.1 years with 41.4% of participants identifying as females. No significant difference was noted between baseline PROMIS pain intensity and interference and grit score ( P = 0.82, P = 0.91, respectively). Three months postoperatively, for those in the ACLR + meniscus repair cohort, low grit ROM was 130 degrees (interquartile range = 10 degrees), whereas high grit ROM was 135 degrees (interquartile range = 8 degrees) ( P = 0.006). CONCLUSIONS: This study found no differences in pain scores at presentation between grit cohorts but found that patients with grit scores below the 50th percentile undergoing ACLR + meniscus repair have 5 degrees less total ROM at 3 months compared with those with high grit scores. Quicker ROM recovery in patients with high grit may be a leading indicator of these patients' likelihood to achieve other postoperative milestones and meet criteria for RTS more quickly; the relationship between grit and readiness for RTS should be further investigated. LEVEL OF EVIDENCE: Level IV; retrospective cohort study.

Availability of Consumer Prices for Arthroscopic Meniscus Surgery.

The purpose is to examine the availability of consumer pricing information for arthroscopic meniscal surgery in the United States. Secondary objectives were comparing the price of meniscal repair to meniscectomy and regional pricing differences. Orthopaedic sports medicine clinics were sorted by state and randomly selected from American Orthopaedic Society for Sports Medicine's online directory. Following standardized script, each clinic was called a maximum of three times to obtain pricing information for meniscal surgery. A total of 1,008 distinct orthopaedic sport medicine practices were contacted. Six (6%) clinics were able to provide complete bundle pricing, and 183 (18.2%) clinics were able to provide physician-only fees for either meniscectomy or meniscal repair. Physician-only fees and bundle pricing were significantly less for meniscal repairs as compared to meniscectomies. There were no geographic regional differences in pricing for physician-only fees. There is a paucity of information regarding price transparency for arthroscopic meniscal surgery. (Journal of Surgical Orthopaedic Advances 32(2):083-087, 2023).

Using Single Peroneal Longus Tendon Graft for Segmental Meniscus Transplantation and Revision Anterior Cruciate Ligament Combined Anterolateral Reconstruction.

This case report describes a new approach to segmental meniscal reconstruction using a peroneal longus autograft in a patient with recurrent traumatic medial meniscus tear and anterior cruciate ligament reconstruction (ACLR) failure. While allograft meniscal transplantation is the preferred method for treating meniscal deficiency, its high cost and various legal regulations have limited its widespread use. Autologous tendon grafts have been proposed as a substitute for allograft meniscus transplantation, but their initial results were poor, leading to little progress in this area. However, recent animal experiments and clinical studies have demonstrated promising results in using autologous tendon grafts for meniscal transplantation, including improvements in pain and quality of life for patients. Further research is needed to evaluate the effectiveness of segmental meniscal reconstruction using autologous tendon grafts, but it could potentially lead to more accessible and cost-effective treatment options for patients with meniscal deficiency.

Editorial Commentary: Meniscal Repair, When Possible, Is Better for Patients Than Meniscectomy.

Patients do not do as well after meniscectomy as after repair. Although saving the meniscus is not always easy and the success rate of repair is not 100%, repair-when possible-remains the best option for patients in the long run. Meniscal repair rates are on the rise, especially in younger patients, but are not high enough. Recent research has shown that more than 95% of meniscal procedures are partial meniscectomies. Improved surgical techniques and instrumentation, as well as a continued increase in understanding the importance of repair, are leading to an increase in meniscal repair rates. Preserve as much meniscus as possible and as often as possible.

Several Techniques Exist With Favorable Biomechanical Outcomes in Radial Meniscus Tear Repair-A Systematic Review.

PURPOSE: To compare biomechanical properties of various radial tear repair techniques in the medial and lateral menisci. METHODS: A search was performed for key words regarding mechanical properties of repair of radial meniscal tears in PubMed, Embase, CINAHL, Scopus, and Cochrane databases, yielding 1791 articles. Articles were screened using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines against inclusion criteria and underwent Methodological Index for Non-Randomized Studies (MINORS) methodologic quality assessment. Repair constructs evaluated were classified based on repair technique, use of a transtibial augmentation, and the number, orientation, and pattern of stitches. Results published across different studies were compared but not subjected to meta-analysis due to variability in testing procedures and heterogeneity of repair methods. RESULTS: We identified 20 studies that performed mechanical testing on 21 different radial meniscal tear repair techniques. The greatest reported mean load-to-failure (LtF) were the transtibial 2-tunnel + 4 horizontal inside-out sutures (191.2 N ± 17.3, cadaver) and all-inside double vertical repair (146.3 N ± 36.2, porcine). The transtibial technique improved LtF and displacement of an inside-out (IO) horizontal repair. All-inside vertical repairs demonstrated greater LtF, stiffness, and displacement compared with IO horizontal repairs in 2 studies. Compared with IO double horizontal repairs, all-inside double vertical or IO double horizontal repairs with reinforcing stitches parallel to the tear exhibited greater LtF in 3 studies and stiffness in 2 studies. Two studies reported that parallel reinforcing stitches significantly reduced suture tear-through compared with similar, nonreinforced repairs. Mean MINORS score for all studies analyzed was 19.88 ± 1.47 points. CONCLUSIONS: A systematic review demonstrated that there may be alternatives to traditional IO horizontal repairs for radial meniscus tears. Less-invasive all-inside vertical techniques reinforced with suture parallel to the tear instead of standard IO horizontal sutures may improve strength of repair. In addition, transtibial 2-tunnel augmentation may also increase strength of radial meniscus tear repairs. CLINICAL RELEVANCE: There may be alternatives to IO horizontal repairs for radial meniscus tears.