Meniscal Allograft Transplantation Research Articles

Imaging of meniscal allograft transplantation: what the radiologist needs to know.

Meniscal allograft transplantation is an emerging surgical option for younger patients with symptomatic meniscal deficiency, which aims to restore anatomic biomechanics and load distribution in the knee joint, and by so doing to potentially delay accelerated osteoarthritis. In this review article, we summarize the structure and biomechanics of the native meniscus, describe indications and procedure technique for meniscal allograft transplantation, and demonstrate the spectrum of expected postoperative imaging and role of imaging to identify potential complications.

Meniscal allograft transplantation in The Netherlands: long-term survival, patient-reported outcomes, and their association with preoperative complaints and interventions

PurposeEvaluation of survival of meniscal allograft transplantation (MAT) and postoperative patient-reported outcome (PRO), and their association with prior interventions of the knee.MethodsA prospective consecutive study of 109 consecutive patients who had an arthroscopic meniscal allograft transplantation (MAT) between 1999 and 2017 by a single surgeon. Patients were assessed with KOOS scores, preoperative and after a minimal follow-up of 2 years. Furthermore, two anchor questions (whether expectations were met and overall satisfaction, on a five-point Likert scale) were asked. Additionally, prior interventions to MAT were evaluated.ResultsPrior to MAT, patients had undergone an average of 2.8 (range 1–14) of surgical procedures of the knee. Overall, mean allograft survival was 16.1 years (95% CI 14.8–17.5 years). Higher age at surgery was associated with lower MAT survival: hazard ratio for MAT failure was 1.19 per year increase (95% CI 1.04 to 1.36, p = 0.009). At 4.5 years (IQR, 2–9) of follow-up, all KOOS score were still improved compared to baseline. Age below 35 years, simultaneous anterior cruciate ligament reconstruction and number of knee surgeries before MAT were associated with lower KOOS scores. Overall patient expectations and overall satisfaction after MAT were not associated with preoperative patient characteristics nor with the number or kind of preoperative interventions.ConclusionMeniscal allograft transplantation has a good overall survival with a clinically relevant improvement. Both meniscal allograft survival and PRO were associated with age. PRO was lower in patients younger than 35 years at time of MAT and meniscal allograft survival was worse in patients older than 50 years. PRO was associated with preoperative patient characteristics and number of surgical procedures prior to MAT. All patients reported improved postoperative satisfaction and met expectations after MAT, both independent of the preoperative history of knee interventions.Level of evidenceLevel III.Trial registration Medical ethical review board (METC) number: 17–104 (7 August 2017).Dutch Trial Register (NTR) number: NTR6630 (4 July 2017).

An Up-to-Date Review of the Meniscus Literature: A Systematic Summary of Systematic Reviews and Meta-analyses.

Background:A large number of systematic reviews and meta-analyses regarding the meniscus have been published.Purpose:To provide a qualitative summary of the published systematic reviews and meta-analyses regarding the meniscus.Study Design:Systematic review; Level of evidence, 4.Methods:A systematic search of all meta-analyses and systematic reviews regarding the meniscus and published between July 2009 and July 2019 was performed with PubMed, CINAHL, EMBASE, and the Cochrane database. Published abstracts, narrative reviews, articles not written in English, commentaries, study protocols, and topics that were not focused on the meniscus were excluded. The most pertinent results were extracted and summarized from each study.Results:A total of 332 articles were found, of which 142 were included. Included articles were summarized and divided into 16 topics: epidemiology, diagnosis, histology, biomechanics, comorbid pathology, animal models, arthroscopic partial meniscectomy (APM), meniscal repair, meniscal root repairs, meniscal allograft transplantation (MAT), meniscal implants and scaffolds, mesenchymal stem cells and growth factors, postoperative rehabilitation, postoperative imaging assessment, patient-reported outcome measures, and cost-effectiveness. The majority of articles focused on APM (20%), MAT (18%), and meniscal repair (17%).Conclusion:This summary of systematic reviews and meta-analyses delivers surgeons a single source of the current evidence regarding the meniscus.

All-Arthroscopic Meniscal Allograft Transplantation Technique with Bone Plugs and Preloaded Sutures

The meniscus is an essential structure for the knee functioning and survival. Meniscectomy is the most common surgical procedure in orthopaedic surgery. Following total or subtotal meniscectomy, meniscal allograft transplantation (MAT) should be considered in symptomatic active young patients. Several MAT techniques have been described in the literature as an attempt to restore normal knee kinematics and potentially decrease the risk of developing knee osteoarthritis. The purpose of this article is to describe in detail an efficient and reproducible all-arthroscopic MAT technique with bone plugs and preloaded sutures.

Staged meniscal allograft transplantation as a biologic treatment of the meniscal deficient knee: A prospective case series of 26 patients with maximum 88-month follow-up

IntroductionThe meniscal deficient knee often exists within the setting of associated pathology including instability, malalignment and chondral injury. The aim of this study was to establish the role of meniscal allograft transplantation (MAT) as part of a staged approach to treatment of the previously menisectomised knee and report: (a) primary data endpoints (pre and post-operative Knee Injury and Osteoarthritis outcome scores (KOOS), Tegner scores, satisfaction scores and graft survival), and (b) secondary endpoints:(complication/reoperation rates, and meniscal extrusion measurements as determined by MRI). Material and methodsThis prospective study included all patients that underwent arthroscopic fresh frozen allograft MAT at our institution (2010–2017) using a soft tissue fixation technique. ResultsTwenty-seven MAT procedures were performed in 26 patients (16 lateral, 11 medial). Ten patients underwent ACL reconstruction, three ACI and two osteotomy in the pre-MAT phase. Seven patients underwent ACI within the post-operative phase. Post-operative mean KOOS scores improved significantly in all subscales (p < .002) as did Tegner scores (p < .05). Graft survival was 100%, satisfaction rate 92%, and mean meniscal extrusion 3.04 mm. Post operatively, three patients required meniscal repair and a single patient, partial menisectomy of graft. Two patients underwent arthroscopic arthrolysis following MAT. ConclusionsThis series highlights the multifactorial profile of the meniscal deficient knee and the role of MAT as a safe and reliable technique in the staged and comprehensive biologic treatment available to minimise symptoms and maximise outcomes.Level of evidence: 4.

Unicompartmental bipolar osteochondral and meniscal allograft transplantation is effective for treatment of medial compartment gonarthrosis in a canine model.

Osteochondral allograft (OCA) transplantation can restore large articular defects in the knee. Bipolar OCA transplantations for partial and whole joint resurfacing often have less favorable results than single-surface transplants. This study was designed to use a large animal model to test the hypothesis that unicompartmental bipolar osteochondral and meniscal allograft transplantation (BioJoint) would be as or more effective for treatment of medial compartment osteoarthritis (OA) compared to standard-of-care nonoperative treatment. OA was induced in one knee of each research hound (n = 8) using a meniscal release model and pretreatment assessments were performed. After 3 months, dogs were randomly assigned to either the control group (n = 4, no surgical intervention, daily nonsteroidal antiinflammatory drugs [NSAIDs]) or the BioJoint group (n = 4). Clinical, radiographic, and arthroscopic assessments were performed longitudinally and histopathology was evaluated at the 6-month endpoint. At study endpoint, functional, pain, and total pressure index measures, as well as radiographic and arthroscopic grading of graft appearance and joint health, demonstrated superior outcomes for BioJoints compared to NSAID controls. Furthermore, histologic assessments showed that osteochondral and meniscal transplants maintain integrity and integrated into host tissues. Clinical significance: The results support the safety and efficacy of unicompartmental bipolar osteochondral and meniscal allograft transplantation in a preclinical model with highly functional outcomes without early OA progression.

Medial and Lateral Meniscus Allograft Transplantation Showed No Difference With Respect to Graft Survivorship and Clinical Outcomes: A Comparative Analysis With a Minimum 2-Year Follow-Up

To compare the differences with respect to clinical and graft survivorship and patient-reported outcomes (PROs) between lateral (LMAT) and medial (MMAT) meniscus allograft transplantation. Patients having a primary MAT between 1998 and 2016 were enrolled. The inclusion criteria were (1) patients who had a minimum 2-year follow-up and (2) patients who had magnetic resonance imaging (MRI) >2 years after surgery. Knees with localized grade 4 articular cartilage lesions >3 cm2 at the time of MAT were excluded. Clinical failure was defined as follows: modified Lysholm score <65, meniscectomy >50% of the graft, meniscectomy to the meniscocapsular junction zone, conversion to revision MAT, or realignment osteotomy or arthroplasty. Graft failure was defined as follows: tears involving >50% of the graft or unhealed peripheral rim observed on MRI. Kaplan-Meier survival analysis with log-rank test was used to compare survivorship between LMAT and MMAT. Patient-reported outcomes were compared based on the Hospital for Special Surgery, modified Lysholm, and International Knee Documentation Committee subjective scores collected preoperatively and at the final follow-up. A total of 299 knees (249 LMAT, 50 MMAT, mean age 33.0 ± 9.8 years) were included. Twenty clinical [2 MMAT (4.0%), 18 LMAT (7.2%)] and 24 graft [2 MMAT (4.0%), 22 LMAT (8.8%)] failures were identified. The mean clinical follow-up period was 63.1 ± 43.1 months (range 2 to 248), and MRI follow-up period was 62.6 ± 43.8 months (range 2 to 248). No significant differences in clinical and graft survivorship were found between the LMAT and MMAT groups (P= .481, P= .271, respectively). PROs preoperatively and at last follow-up also showed no significant difference between the groups. No significant differences in clinical survivorship, graft survivorship, and PROs were found between the LMAT and MMAT groups. Level III, retrospective comparative study.

Meniscal Allograft Transplantation After Anterior Cruciate Ligament Reconstruction Can Improve Knee Stability: A Comparison of Medial and Lateral Procedures

Background: The purpose of this study was to evaluate the clinical score and stability after meniscal allograft transplantation (MAT) after a previous anterior cruciate ligament (ACL) reconstruction. Hypothesis: Medial MAT would improve anteroposterior stability, and lateral MAT would improve rotational stability. Study Design: Cohort study; Level of evidence, 3. Method: We retrospectively investigated 31 cases of MAT after a previous total or nearly total meniscectomy and ACL reconstruction between November 2008 and June 2017. Cases were divided into medial (16 cases) and lateral (15 cases) MAT groups. The patients were assessed preoperatively and at the 2-year follow-up. Results: In the medial MAT group, the International Knee Documentation Committee, Lysholm, Lysholm instability, and Tegner scores improved significantly at the 2-year follow-up, and there were also significant improvements in the anterior drawer, Lachman, and pivot-shift tests. In the lateral MAT group, the Lysholm and Tegner scores improved significantly at the 2-year follow-up, as had the anterior drawer and Lachman tests but not the pivot-shift test. The medial MAT group showed significant improvement in side-to-side difference on Telos stress radiographs, from 6.5 mm (preoperatively) to 3.6 mm (2-year follow-up) (P = .001), while the lateral MAT group showed no significant change. There was no progression of arthritis in either group. Conclusion: Medial MAT improved not only anteroposterior stability but also rotational stability in the meniscus-deficient ACL-reconstructed knee. Lateral MAT showed improvements in the anterior drawer and Lachman tests but not in the pivot-shift test or side-to-side difference on Telos stress radiographs in meniscus-deficient ACL-reconstructed knees. Instability and pain are indications for MAT in meniscus-deficient ACL-reconstructed knees.

Lateral meniscal allograft transplantation and stabilisation in a dog with stifle subluxation

This case describes the clinical features and the favourable clinical outcome after a lateral meniscal allograft transplant and stifle stabilisation in a dog that suffered a significant injury to its...

Extrusions do not affect degenerative morphologic changes in lateral meniscus allografts during midterm follow-ups.

To investigate degenerative morphological changes in meniscus allograft after lateral meniscus allograft transplantation (MAT) based on extrusions. Ninety-one patients who underwent lateral MAT were divided into extruded and non-extruded groups. Serial magnetic resonance imaging scans obtained 6weeks, 1year, and at the last follow-up (midterm, 3-7years) post-surgery were evaluated retrospectively. Degenerative morphological changes at each time point in each group were compared using the postoperative meniscal width, thickness, and intrameniscal signal intensity (IMSI) at the anterior horn, mid-body, and posterior horn. The Lysholm scores and meniscal tears based on graft extrusion were also investigated. The mean age was 33.7 ± 11.1years (64 men and 27 women). Fifty-three (58%) and 38 knees (42%) were classified into the non-extruded and extruded groups, respectively. The overall meniscal width of the mid-body decreased from 9.6 ± 1.3 to 6.5 ± 1.2mm (p < 0.01), and IMSI of mid-body was increased from 1.2 ± 0.1 to 1.7 ± 0.1 (p < 0.01) during midterm follow-ups. No significant differences were observed between the meniscal width, thickness, and IMSI at the anterior horn (n.s.), mid-body (n.s.), and posterior horn (n.s.) of the two groups during the midterm follow-ups. The incidence of meniscus tears and Lysholm scores did not differ significantly between the groups during midterm follow-ups. The overall meniscus width of mid-body decreased while the relative IMSI of mid-body increased during midterm follow-ups after lateral MAT. Meniscal allograft extrusions did not influence postoperative changes in meniscus width, thickness, and relative intrameniscal signal intensity. Level III.

Correlation analysis of potential factors influencing graft maturity based on MRI after lateral meniscal allograft transplantation

The aim of this respective study was to assess the graft signal/noise quotient (SNQ) value and associated factors based on magnetic resonance imaging (MRI) after lateral meniscal allograft transplantation (LMAT). Patients with LMAT were included. The SNQ, width of the anterior horn (WAH), width of the midbody (WMB), width of the posterior horn (WPH) of each lateral meniscus, coronal graft extrusion (CGE), the anterior cartilage meniscus distance (ACMD) and the posterior cartilage meniscus distance (PCMD) were measured using MRI and tested by multivariate stepwise regression analysis. The relative percentage of extrusion (PRE) was calculated. Seventy-one male patients were examined, and 7 patients were lost to follow-up. The SNQ of the meniscus increased from immediately after surgery to 6 months postoperatively, decreased from 6 to 12 months, increased from 12 to 24 months, and increased from 24 to 36 months. The mean SNQ had a significant negative association with the WPH and CGE at 6 months (p < 0.05), the WPH at 1 year (p < 0.05), the PRE of CGE (CPRE) at 2 years (p < 0.05), and the PCMD, CPRE, and PRE of the PCMD (PPRE) at 3 years (p < 0.01) postoperatively. Multivariate stepwise regression analysis showed that the WPH at 6 months, WPH at 1 year, WMD and PCMD at 2 years, and WMD, ACMD and CGE at 3 years were significant independent factors correlated with the mean SNQ of grafts in different periods. Maturation of meniscal grafts fluctuated with time. The maturation process occupied the main role before 1 year postoperatively, but after the maturation process, tearing of the meniscal allograft played the leading role. Changes in an allograft’s location had an obvious association with the SNQ. The WPH influenced the graft SNQ value at 6 months and 1 year postoperatively, but after the maturation process, the WMB and graft extrusion played the same roles.

Reoperation Rates Following Meniscus Transplantation Using the Truven Database

The purpose of this study was to determine the (1) reoperation rate and (2) 30-day complication rate in a large insurance database. The Truven Database was queried for subjects that underwent meniscus allograft transplantation (Current Procedural Terminology code 29868) in the outpatient setting with minimal 2-year follow-up. Patients without confirmed laterality and patients that underwent concomitant ligament reconstruction were excluded. Reoperation was defined by ipsilateral knee procedure after the index surgery. The 30-day postoperative complication rates were assessed using International Classification of Diseases, 9th Revision, Clinical Modification codes. A total of 284 patients (mean age of 26.2 ± 10.4 years; 49.6% females) were included in this study with mean follow up of 43.2 ± 19.2 months. One hundred and sixty-seven subjects (58.8%) undergoing meniscus allograft transplantation underwent reoperation at an average of 11.9 ± 12.2 months postoperatively. There was a low number of subjects that required ipsilateral unicompartmental knee arthroplasty and total knee arthroplasty postoperatively (0.7% and 1.1%, respectively). The overall 30-day complication rate following meniscus allograft transplantation was 1.4%. Patients undergoing meniscus allograft transplantation have a 58.8% reoperation rate at final follow up with low (1.4%) 30-day complication rates in a large insurance database. Level IV, case series.

Long-term Outcomes and Survivorship of Fresh-Frozen Meniscal Allograft Transplant With Soft Tissue Fixation: Minimum 10-Year Follow-up Study

Background: Meniscal allograft transplant (MAT) is considered an effective procedure for reducing pain and improving knee function. Nevertheless, the current knowledge regarding the results of MAT is limited to short- to mid-term follow-up studies, especially for arthroscopic techniques. Purpose: To evaluate the long-term clinical outcomes, reoperations, and failures with a minimum follow-up of 10 years after fresh-frozen MAT performed arthroscopically with soft tissue fixation. Study Design: Case series; Level of evidence, 4. Methods: A total of 46 patients (age, 36.6 ± 10.6 years; 36 male, 10 female) who underwent medial MAT (n = 27) or lateral MAT (n = 19) with a minimum 10-year follow-up were evaluated with the Lysholm score, Knee injury and Osteoarthritis Outcome Score (KOOS), visual analog scale for pain, and Tegner score. Surgical failure was defined as the need for partial or total graft removal (meniscectomy or knee replacement), and clinical failure was defined as the need for partial or total graft removal in addition to a poor Lysholm score (<65 points) at final follow-up. Survival analysis was performed with Kaplan-Meier curve, and clinical scores were analyzed based on the Patient Acceptable Symptom State (PASS) for MAT. Results: 10-year survival and clinical data were available for 38 patients. Because 6 meniscectomies were required, the rate of survival free from surgical failure was 91% at 5 years and 86% at 10 years. Lower survival was reported in lateral MAT (73%) compared with medial MAT (96%). Because a further 4 patients had poor Lysholm scores, the rate of survival free from surgical and clinical failure was 87% at 5 years and 70% at 10 years. The average Lysholm score at final follow-up was 82 ± 20, and 60% to 82% of patients achieved PASS of the various KOOS subscales. The Tegner score and the KOOS Sport score significantly decreased from mid-term to long-term evaluation (P < .001 and P < .05, respectively). Other KOOS subscales and the Lysholm score remained stable at long-term evaluation. No significant differences were found between isolated MAT or combined MAT regarding subjective scores, surgical failures, or clinical failures. Conclusion: Up to 10 years after surgery, 86% of fresh-frozen MATs with soft tissue fixation were still in situ, and satisfactory clinical results were present for about 70% of patients. Decline of clinical outcomes from midterm to long term was noted only in sports-related scores. A higher number of overall reoperations was noted in female patients, whereas a higher risk of failure was present in the patients with lateral MAT.

Return to Work Following Arthroscopic Meniscal Allograft Transplantation.

Evaluate the ability of patients to return to work (RTW) following arthroscopic meniscal allograft transplantation (MAT) for meniscal deficiency. Consecutive patients undergoing MAT were retrospectively reviewed at a minimum of 2 years postoperatively. Patients completed a subjective work questionnaire, Visual Analogue Scale for pain, Single Assessment Numerical Evaluation, and satisfaction. Forty-seven patients who were employed within 3 years prior to surgery (average age: 30.2 ± 6.9 years) were contacted at an average of 3.5 ± 0.9 years postoperatively. Forty-six patients (97.8%) returned to work by 2.7 ± 2.6 months postoperatively, and 44 patients (93.6%) returned to the same level of occupational intensity. Patients who held sedentary, light, medium, or high intensity occupations were able to RTW at a rate of 100.0%, 100.0%, 88.9%, and 85.7% (P = 0.4) by 1.1 ± 1.0 months, 2.5 ± 2.5 months, 3.5 ± 3.2 months, and 4.3 ± 2.8 months (P = 0.3) postoperatively. Thirty-eight patients (80.9%) were at least somewhat satisfied, and 43 patients (91.5%) would still have the operation if presented the opportunity. No patient underwent revision MAT or conversion to arthroplasty. In patients with painful meniscal deficiency, MAT provides a high rate of RTW (97.8%) by 2.7 ± 2.6 months postoperatively. However, some patients may be unable to return to their previous level of occupational intensity. Although statistically insignificant, patients with higher intensity occupations may have a lower rate and longer duration until RTW than those with less physically demanding occupations. Information regarding RTW is imperative for appropriately managing postoperative expectations.

The Importance of Staging Arthroscopy for Chondral Defects of the Knee.

This study aims to evaluate the role of staging arthroscopy in the diagnosis of knee chondral defects and subsequent surgical planning prior to autologous chondrocyte implantation (ACI), osteochondral allograft transplantation (OCA), and meniscus allograft transplantation (MAT). All patients who underwent staging arthroscopy prior to ACI, OCA, or MAT at our institution from 2005 to 2015 were identified. Medical records were reviewed to document the diagnosis and treatment plan based on symptoms, magnetic resonance imaging (MRI) findings and previous operative records. Operative records of the subsequent staging arthroscopy procedure were reviewed to document the proposed treatment plan after arthroscopy. All changes in treatment plan following staging arthroscopy were recorded. Univariate analyses were performed to identify any significant predictors for likelihood to change. A total of 98 patients were included in our analysis. A change in surgical plan was made following arthroscopy in 36 patients (36.7%). Fourteen patients (14.3%) were found to have additional defects that warranted cartilage restoration surgery. In 15 patients (15.3%), at least one defect that was originally thought to warrant cartilage restoration surgery was found to be amenable to debridement alone. The surgical plan was changed from ACI to OCA in four cases (4.1%) and OCA to ACI in one case (1%). A previously proposed MAT was deemed unwarranted in one case (1%), and a planned meniscal repair was changed to MAT in another (1%). Patient age, sex, and the affected knee compartment were not predictors for a change in surgical plan. Body mass index (BMI) was significantly higher in patients who had a change in surgical plan (29.5 kg/m2) compared with those who did not (26.5 kg/m2). A change in surgical plan was more likely to occur for trochlear lesions (46.4%) compared with other articular surface lesions (p = 0.008). The results of our study indicate that staging arthroscopy is an important step in determining the most appropriate treatment plan for chondral defects and meniscal deficiency, particularly those with trochlear cartilage lesions.

Centralized anterior bone plug results in less graft extrusion in patients undergoing medial meniscus allograft transplantation following anterior cruciate ligament reconstruction

PurposeThis study was performed to analyze the effect of anterior bone plug positioning on clinical and radiological outcomes in patients undergoing medial meniscus allograft transplantation (M-MAT) following anterior cruciate ligament reconstruction (ACLR). MethodsData from 24 patients who underwent M-MAT following meniscectomy and ACLR from November 2008 to June 2017 were retrospectively investigated. Patients were divided into either the centrally positioned group (group C) or the medially positioned group (group M) based on the location of the anterior bone plug for M-MAT. Clinical and radiographic follow-up was performed at two years postoperatively. International Cartilage Repair Society (ICRS) grades of chondral lesion, graft extrusion, and meniscus signal intensity were evaluated by magnetic resonance imaging (MRI) at one year postoperatively. ResultsThere were no significant differences in demographics including follow-up time of two years between the two groups. There were no significant differences in postoperative subjective International Knee Documentation Committee (IKDC), Lysholm, and Tegner scores between groups. Furthermore, there were no significant differences in osteoarthritis progression or ICRS grade on MRI. However, group C showed significantly less absolute graft extrusion (P = .008) and relative graft extrusion (P < .0001) on one-year follow-up MRI, relative to group M. Meniscus signal intensity tended to be better in group C, although this difference was not statistically significant (P = .092). ConclusionThe centrally positioned group showed significantly less graft extrusion on MRI compared to the medially positioned group; however, there were no statistically significant differences in clinical outcomes between the two groups.

Meniscal allograft transplantation: a review of indications, techniques, and outcomes.

When compared to meniscectomy, meniscus allograft transplantation (MAT) may provide superior long-term benefits to young, active patient populations who have lost meniscal function because of irreparable damage, such as, an avascular tear, previous repair failure, and unsalvageable tear types. Positive outcomes are most likely to be achieved when meniscus allograft transplantation is performed in appropriately selected patients. Indications include patients younger than 50years of age, with a history of subtotal or total meniscectomy without concomitant articular cartilage defects, uncorrectable joint malalignment, and/or knee instability. Outcomes for meniscal allograft transplantation are promising with studies reporting long-term graft survivorship as high as 89% at 10years and significant improvements in multiple patient reported outcome measures. LEVEL OF EVIDENCE: Level V.

Does Age Itself Have an Adverse Effect on Survivorship of Meniscal Allograft Transplantation? A Cartilage Status and Time From Previous Meniscectomy–Matched Cohort Study

Background: The aging process is accompanied by several conditions that could affect the outcome of meniscal allograft transplantation (MAT). These conditions have made it difficult for clinicians to determine the effect of chronologic age on survivorship after MAT. Hypothesis: Advanced age does not have an adverse effect on survivorship of MAT when controlling for age-related factors, such as cartilage status and time from previous meniscectomy. Study Design: Cohort study; Level of evidence, 3. Methods: The records of 264 consecutive patients who underwent primary medial or lateral MAT were reviewed. To check whether there was a difference in MAT survivorship according to age, a cutoff value was calculated from a time-dependent receiver operating characteristic curve. Survival rates, as well as clinical improvement as determined using the Lysholm score, were compared between groups divided by the cutoff value. Patients were matched for cartilage status and elapsed time from previous meniscectomy. Differences in survivorship and clinical outcomes were assessed between the matched groups. Results: A time-dependent receiver operating characteristic curve showed that the difference in MAT survivorship was maximized with a cutoff age of 43 years. Kaplan-Meier analysis showed a significant difference in MAT survivorship between the older and younger groups (log-rank test, P = .01). However, after matching for cartilage status and time from previous meniscectomy, which left 56 patients per group, there was no significant difference in MAT survivorship (log-rank test, P = .10) between the groups. Regarding clinical outcomes, the mean Lysholm scores were not significantly different between the older and younger groups (P = .19, before matching; P = .39, after matching). Conclusion: MAT survivorship was more affected by age-related prognostic factors, such as cartilage status and time from previous meniscectomy, than age itself. Clinical outcomes did not show differences according to age, either.

Return to Sport and Patient Satisfaction After Meniscal Allograft Transplantation

To investigate patient return to sport and satisfaction after meniscal allograft transplantation (MAT). Patients undergoing MAT using a bone bridge technique between 2013 and 2015 with minimum 2-year follow-up were retrospectively reviewed. They completed a survey regarding return to sport, satisfaction, and subsequent surgery in addition to patient-reported outcome measures. Of 117 patients, 87 (74.4%) were available at an average follow-up of 3.64 years (range, 2.01-5.13 years). The mean age at the time of surgery was 28.99 ± 8.26 years. Lateral MAT was performed in 44 cases (50.6%); medial MAT, 42 (48.3%); and combined medial and lateral MAT, 1 (1.1%). Concomitant procedures were performed in 72 patients (82.7%) including cartilage restoration (n= 65, 74.7%), realignment (n= 9, 10.3%), and anterior cruciate ligament reconstruction (n= 9, 10.3%). Patients experienced significant improvement in the Lysholm score (P < .001), International Knee Documentation Committee score (P < .001), Knee Injury and Osteoarthritis Outcome Score (KOOS)-Quality of Life (P < .001), KOOS-Activities of Daily Living (ADL) (P < .001), KOOS-Pain (P < .001), KOOS-Sports (P= .001), KOOS-Symptoms (P= .003), Short Form 12 physical score (P < .001), and Veterans Rand-12 physical score (P < .001). Reoperation was performed in 26 patients (29.9%); failure occurred in 12 patients (13.8%; total knee arthroplasty in 1, unicompartmental arthroplasty in 2, and total meniscectomy in 9). Overall, 77.0% of patients were satisfied with their outcome. Prior to MAT, 82 patients (94.3%) participated in sporting activities; 62 patients (75.6%) returned to at least one sport at 12.58 ± 6.20 months postoperatively, with 30 (48.4%) reaching their preoperative level of intensity and 72 (87.8%) discontinuing at least one of their preoperative sports. The most common reasons for sports discontinuation postoperatively were prevention of further damage (73.6%), pain with activity (51.4%), fear of further injury (48.6%), surgeon recommendation (33.3%), and swelling with activity (30.6%). Patients were satisfied with their sports participation at a rate of 62.1%. In a complex patient population undergoing arthroscopic MAT, 75.6% of patients were able to return to at least one sport at an average of 12.58 ± 6.20 months postoperatively. The level of sport declined, with 93.5% of patients restricting involvement to recreational sports after MAT and 48.4% returning to their preoperative level of activity intensity. In addition, 87.8% of patients reported discontinuing a sport in which they had participated preoperatively. The most common reasons for decreasing level of sport were prevention of further damage, pain or swelling with sports, and fear of further injury. The reoperation rate after MAT was 29.9%. Most patients were satisfied with the outcome of surgery, with 77.0% satisfied in general and 62.1% satisfied with their ability to play sports. Level IV, retrospective case series.

High rate of return-to-play following meniscal allograft transplantation.

In recent years, meniscal allograft transplantation (MAT) has been established as an effective option for young patients with symptomatic meniscus insufficiency with goals of functional improvement and joint preservation. Currently, there is little available information on return-to-play among patients in this cohort. The purpose of this study is to systematically review the literature and to evaluate the reported rehabilitation protocols, return-to-play guidelines, and subsequent rates of return-to-play following MAT. MEDLINE, EMBASE and the Cochrane Library were searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to find studies on MAT. Studies were included if they reported return-to-play data or rehabilitation protocols. The rate and timing of return-to-play was assessed. The rehabilitation protocols were recorded, including time to start range of motion (ROM), full ROM, partial weight bearing (WB), and full WB. Overall, 67 studies met the inclusion criteria. Eleven studies, including 624 patients, reported 483 out of 624 patients (77.4%) returning to play, with 326 out of a reported 475 patients (68.6%) returning to the same/higher level, at a mean time to return of 9.0months. There was significant variability in the reported rehabilitation protocols, but the most commonly reported time to begin ROM exercises was within the first week by 42 out of 60 studies (70.0%) and full ROM at 8weeks by 18 out of 46 studies (39.1%). Partial weight bearing was most commonly begun in the fourth week by 20 out of 46 studies (43.5%), and for full WB the sixth week by 43 out of 65 studies (66.1%). Time elapsed following surgery was the most commonly reported criteria for return-to-play by 44 out of 48 studies (91.6%), with 6months being the most common time point utilized by 17 out of 45 studies (37.8%). A small proportion of studies, 16 out of 48 (33.3%), advised against returning to competitive/collision sports altogether following MAT. In conclusion, there is a high rate of return-to-play following MAT, with the majority of patients returning to the same level of play. However, there is significant variability in reported rehabilitation protocols, and poor-quality reporting in return-to-play criteria in the literature indicates a need for further study and the development of an evidence-based consensus statement for this patient population. The results from this study can be used to better inform patients on their expected outcomes and provide a more informed consent process. IV.