Arthroscopic repair of meniscal tears extending into the avascular zone in patients younger than twenty years of age

[Ligamentous and meniscal injuries of the pediatric knee joint]

Intraligamentous injuries to the anterior cruciate ligament (ACL) and meniscus injuries are rare in children and adolescents and often occur as a result of sports injuries. Clinically, they usually present as a hemarthrosis. The diagnosis of choice is the MRI examination. Surgical treatment of intraligamentary ACL injuries using the transphyseal technique is now also the gold standard treatment for children and adolescents, leg axis and length checks are necessary after surgery until growth is complete. Meniscus injuries are also addressed surgically. Postoperative follow-up treatment and rehabilitation are particularly important in order to prevent reinjury. The disc meniscus is a special entity and is also treated surgically if it is symptomatic. Isolated collateral ligament and posterior cruciate ligament ruptures are rarities.

Repair of radial tears of the lateral meniscus on a stable knee: Results at a minimum follow-up of 2 years

INTRODUCTION

In younger patients, meniscal repair is recommended for isolated lateral meniscus tears that are most often due to acute trauma. But there is little published data on the outcomes of repairing this specific type of lesion. The goal of this study was to evaluate the clinical outcomes, report the failure rate of repairing radial tears of the lateral meniscus in stable knees and determine the risk factors for failure.

MATERIALS AND METHODS

All patients who had a stable knee and underwent arthroscopic repair of a radial lateral meniscus tear between April 2013 and December 2019 were reviewed retrospectively. Failure was defined as revision surgery for recurrence of symptoms (pain, locking) with intraoperative confirmation that the meniscus did not heal. The following data were collected: demographics (age, sex, BMI), time to surgery, clinical outcome scores (Tegner, Lysholm, IKDC), surgical details (repair technique, lesion zone, number of sutures).

RESULTS

Thirty patients were included having a mean age of 20.1years (14-31). The follow-up ranged from 24 to 110months (mean 66.8±25.2). An all-inside repair was done in 6 patients (20%); an outside-in technique was done in 17 patients (57%) and a combination of all-inside and outside-in was done in 7 patients (23%). Four patients (13%) had a recurrence of their symptoms later on, while participating in sports. All the recurrences were at the initial tear site. The time to revision surgery was 16, 19, 24 and 37months in these four patients (mean 24±9). All the other patients were able to resume sports at their pre-injury level. Significant improvement in the IKDC, Lysholm and Tegner functional scores were found between the preoperative and postoperative assessments. No statistically significant risk factors for failure were identified.

DISCUSSION

The functional healing rate after repair of a radial lateral meniscus tear in a stable knee was 86% at a mean follow-up of 5years, with the surgical technique having no impact on the long-term result. Most of the failures occurred within 2years of the repair procedure. We recommend repairing these tears as they have considerable healing potential.

LEVEL OF EVIDENCE

IV; retrospective observational cohort study.

More Is Not Merrier: Increasing Numbers of All-Inside Implants Do Not Correlate with Higher Odds of Revision Surgery

The purpose of this study was to evaluate the relationship between the number of all-inside meniscal repair implants placed and the risk of repair failure. We hypothesized that the use of higher numbers of all-inside meniscus repair implants would be associated with increased failure risk. A retrospective chart review identified 351 patients who underwent all-inside meniscus repair between 2006 and 2013 by a sports medicine fellowship-trained orthopaedic surgeon at a single institution. Patient demographics (age, body mass index [BMI], sex) and surgical data (number of implants used, concomitant anterior cruciate ligament reconstruction [cACLR], and tear type/size/location) were recorded. Patients who received repairs in both menisci or who had follow-up < 1-year postoperatively were excluded. Repair failure was identified through chart review or patient interviews defined as a revision surgery on the index knee such as partial meniscectomy, total knee arthroplasty, meniscus transplant, or repeat repair. Logistic regression modeling was utilized to evaluate the relationship between the number of implants used and repair failure. A total of 227 all-inside meniscus repairs were included with a mean follow-up of 5.0 ± 3.0 years following surgery. Repair failure was noted in 68 knees (30.3%)-in 28.1% of knees with fewer than four implants and in 35.8% of knees with four or more implants (p = 0.31). No significant increase in failure was observed with increasing number of all-inside medial (odds ratio [OR]: 1.15; 95% confidence interval [CI]: 0.79-1.7; p = 0.46) or lateral (OR: 0.86; 95% CI: 0.47-1.57; p = 0.63) implants after controlling for patient age, BMI, cACLR, tear type, or size. Tears of the lateral meniscus located in the red-white and white-white zones had lower odds of failure (OR: 0.14; 95% CI: 0.02-0.88; p = 0.036) than tears within the red-red zone, and patients with cACLR had lower odds of repair failure (OR: 0.40; 95% CI: 0.18-0.86, p = 0.024) than those without. The number of all-inside implants placed during meniscus tear repair did not affect the likelihood of repair failure leading to reoperation after controlling for BMI, age, tear type, size, location, and cACLR. LEVEL OF EVIDENCE:  III.

Greater rate of return to play and re-injury following all-inside meniscal repair compared to the inside-out technique: a systematic review

INTRODUCTION

Inside-out and all-inside arthroscopic meniscal repairs are widely performed. However, it remains unclear which method promotes greater clinical outcomes. This study compared inside-out versus all-inside arthroscopic meniscal repair in terms of patient-reported outcome measures (PROMs), failures, return to play, and symptoms.

METHODS

This systematic review was conducted in accordance with the PRISMA guidelines. Two authors independently performed the literature search by accessing the following databases: PubMed, Google Scholar, and Scopus in February 2023. All clinical studies which investigated the outcomes of all-inside and/or inside-out meniscal repair were considered.

RESULTS

Data from 39 studies (1848 patients) were retrieved. The mean follow-up was 36.8 (9 to 120) months. The mean age of the patients was 25.8 ± 7.9 years. 28% (521 of 1848 patients) were women. No difference was found in PROMs: Tegner Activity Scale (P = 0.4), Lysholm score (P = 0.2), and International Knee Document Committee score (P = 0.4) among patients undergoing meniscal repair with all inside or inside-out techniques. All-inside repairs showed a greater rate of re-injury (P = 0.009) but also a greater rate of return to play at the pre-injury level (P = 0.0001). No difference was found in failures (P = 0.7), chronic pain (P = 0.05), reoperation (P = 0.1) between the two techniques. No difference was found in the rate of return to play (P = 0.5) and to daily activities (P = 0.1) between the two techniques.

CONCLUSION

Arthroscopic all-inside meniscal repair may be of special interest in patients with a particular interest in a fast return to sport, while, for less demanding patients, the inside-out suture technique may be recommended. High-quality comparative trials are required to validate these results in a clinical setting.

LEVEL OF EVIDENCE

Level III, systematic review.

Total Knee Arthroplasty After Meniscectomy Is More Likely in Patients With Bicompartmental or Complex Tears

Purpose

To determine the relationship between meniscus tear morphologies, stratified by location and pattern, and knee arthroplasty rates in a commercial insurance population.

Methods

The PearlDiver database was queried for patients ≥35 years old with a meniscus tear of specified laterality and ≥2 years follow-up between 2015 and 2018. Two analyses were conducted with cohorts matched on age, sex, Charlson Comorbidity Index, obesity, osteoarthritis (OA), and treatment (meniscectomy vs conservative): one with equal-sized subgroups by tear location (medial only, lateral only, or both medial and lateral) and another by tear pattern (bucket-handle, complex, or peripheral). The rate of subsequent total knee arthroplasty (TKA) was compared between matched groups.

Results

In total, 129,987 patients (mean age: 57.8 ± 10.5 years) were matched by tear location; 1,734 patients with medial-only tears (4.0%), 1,786 with lateral-only tears (4.1%), and 2,611 with medial plus lateral tears (6.0%) underwent a TKA within 5 years (P < .001). Patients with both medial and lateral tears were 1.55-fold more likely to undergo TKA. In total, 24,213 patients (mean age: 56.0 ± 10.5 years) were matched by tear pattern; 296 patients with bucket-handle tears (3.7%), 373 with complex tears (4.6%), and 336 with peripheral tears (4.2%) underwent TKA (P = .01). Patients with complex tears were 1.29-fold more likely to undergo TKA than patients with bucket-handle tears (P = .002).

Conclusions

In matched cohorts of patients with degenerative meniscus tears, having both medial plus lateral tears conferred a 1.5-fold risk of TKA, whereas complex tears conferred a 1.3-fold risk within 5 years. Specific meniscal tear patterns and locations harbor varying risk in progressing to end-stage knee OA, and these data may help counsel patients about their likelihood of progressing to end-stage OA warranting an arthroplasty procedure.

Level of Evidence

Level III, retrospective comparative study.

Bucket-Handle Meniscus Tear Management With Meniscectomy Versus Repair Correlates With Patient, Socioeconomic, and Hospital Factors

INTRODUCTION

Bucket-handle meniscus tears are common knee injuries that are often treated surgically with meniscectomy or meniscal repair. Although clinical factors may influence the choice of one treatment approach over the other, the influence of patient, socioeconomic, and hospital factors remains poorly characterized. This study aimed to estimate the relative nationwide utilization of these two procedures and delineate a variety of factors that are associated with the selection of one treatment approach over the other.

METHODS

Meniscal repair and meniscectomy procedures conducted for isolated bucket-handle meniscus tears in 2016 and 2017 were identified in the Nationwide Ambulatory Surgery Sample database. Cases were weighted using nationally representative discharge weights. Univariate analyses and a multivariable logistic regression model were used to compare patient, socioeconomic, and hospital factors associated with meniscal repair versus meniscectomy.

RESULTS

In total, 12,239 cases were identified, which represented 17,236 cases after weighting. Of these, meniscal repair was conducted for 4,138 (24.0%). Based on the logistic regression model, meniscal repair was less likely for older and sicker patients. By contrast, several factors were associated with markedly higher odds of undergoing meniscal repair compared with meniscectomy. These included urban teaching hospitals; geographic location in the midwest, south, and west; and higher median household income.

DISCUSSION

Using a large nationally representative cohort, the current data revealed that only 24.0% of surgically treated bucket-handle meniscus tears were treated using repair. Identification of patient, socioeconomic, and hospital factors differentially associated with meniscal repair suggest that other factors may systematically influence surgical decision-making for this patient population. Surgeons should be conscious of these potential healthcare disparities when determining the optimal treatment for their patients.

LEVEL OF EVIDENCE

Level III.

Rehabilitation and return to sports after isolated meniscal repairs: a new evidence-based protocol

PURPOSE

Despite many protocols that have been proposed, there's no consensus in the literature regarding the optimal rehabilitation program and return to sports (RTS) protocol following isolated meniscal repair. The aim of this current concept review is to look at the evidence of rehabilitation and RTS program after isolated meniscal repair, focusing on general and specific protocols per type of injury trying to give some guidelines based on the current state of knowledge.

METHODS

A narrative literature review was performed searching PubMed database to identify relevant articles from January 1985 to October 2021 on rehabilitation and RTS after isolated meniscal repair. Randomized controlled trials (RCTs), prospective and retrospective cohort studies, case series, systematic reviews, meta-analyses, cadaveric studies and basic science studies were included.

RESULTS

When the hoop tensile stress effect is preserved, an accelerated rehabilitation program may be suggested. Hence, partial weight bearing (20 kg) in association with ROM limited to 90° is allowed for the first four weeks, followed by weight bearing as tolerated. In contrast, when circumferential hoop fibers are disrupted, a restricted rehabilitation protocol may be recommended. In this scenario no weight bearing is allowed for the first six weeks after the surgery and range of motion (ROM) is limited to 90°.

CONCLUSION

Biomechanical evidence suggests that tailoring an individualized protocol based upon the type of lesion and meniscus stability is reasonable.

LEVEL OF EVIDENCE

Level V.

Higher healing rate after meniscal repair with concomitant ACL reconstruction for tears located in vascular zone 1 compared to zone 2: a systematic review and meta-analysis

PURPOSE

The purpose of this study was to determine and compare the percentage of completely healed meniscal tears after arthroscopic repair combined with anterior cruciate ligament reconstruction (ACLR) for the different vascular zones of the meniscus.

METHODS

PubMed, Embase, Web of Science, Cochrane library and Emcare were searched on 19 May 2020 for articles reporting healing rates after arthroscopic meniscal repair with concomitant ACLR for the different meniscal vascular zones as assessed by second-look arthroscopy. Data on meniscal tears were extracted as located in zones 1, 2 or 3, according to the Cooper classification. Studies were graded in quality using a modified Newcastle-Ottawa Scale. Pooled analyses were performed utilizing a random-effects model. Meta-analyses were performed using R version 3.6.2 and SPSS statistical software version 25.0. The study was registered with PROSPERO (ID:CRD42020176175).

RESULTS

Ten observational cohort studies met the inclusion criteria, accounting for 758 meniscal tear repairs in total. The pooled overall proportion of healing was 78% (95% CI 72-84%). The mean weighted proportion of healing was 83% (95% CI 76-90%) for studies (n = 10) reporting zone 1 tears and 69% (95% CI 59-79%) for studies (n = 9) reporting zone 2 tears. No study reported healing rates for zone 3 tears. The pooled overall odds ratio was 2.5 (95% CI 1.00-6.02), indicating zone 1 tears as 2.5 times more likely to heal than zone 2 tears.

CONCLUSION

This study demonstrates that meniscal tears localized in vascular zone 1 were more likely to heal than those in zone 2.

LEVEL OF EVIDENCE

IV.

Evidence-based rationale for treatment of meniscal lesions in athletes

Meniscal injuries in elite athletes are a common cause of missed game time and even have the potential to be career shortening. In this patient group, care must be paid not only to the pathology, but also to a player's contract status, time in the season, specific demands of his/her sport and position on the field, and future consequences. Successful treatment requires the clinician to understand the player's goals and needs, communicate effectively between all stakeholders, and a have knowledge of the challenges posed by the different types of meniscal tear seen in this population. Paramount is the distinction between injuries to the medial and lateral meniscus. Deficiency of the lateral meniscus, as a result of a tear or a meniscectomy, leads to frequent early problems and inexorably to chondral degeneration thereby affecting an athlete's ability to perform. Therefore, it is strongly recommended to repair the majority of lateral meniscal tears. Medial meniscal tears pose a more challenging treatment dilemma, as the success of partial meniscectomy in achieving reproducible, early return to play must be balanced against the long-term degenerative consequences. Many meniscal tears are correctly treated non-operatively.Level of evidence V.

Outcomes of pediatric anterior cruciate ligament reconstructions in patients with and without bucket handle meniscus repairs

The purpose of this study was to report the outcomes of concomitant bucket handle meniscal tear (BHMT) repair and anterior cruciate ligament (ACL) reconstruction and to compare the outcomes with those after isolated ACL reconstruction in patients aged ≤16 years. Patients in our database from 2013 to 2017 were retrospectively analyzed. Patients were assigned to one of two treatment groups based on the presence of BHMTs: no meniscal tear group (group A) and BHMT group (group B). All BHMTs were repaired using the combined inside-out with all-inside technique. This study included 64 knees divided into two groups: 47 knees in group A and 17 knees in group B. There was a significant difference in the interval between ACL injury and surgery between groups A and B (69 vs. 150 days, respectively; P < 0.001). Mean postoperative International Knee Documentation Committee and Lysholm scores in group A were slightly, although significantly, improved compared to those in group B (96.5 vs. 92.6, respectively; P < 0.05, and 98 vs. 95, respectively; P < 0.05). There were no significant differences in postoperative anteroposterior laxity and graft failure rate between the groups. In group B, four patients (23.5%) required surgery for incomplete meniscal healing. Postoperative International Knee Documentation Committee and Lysholm scores of patients with BHMTs were significantly lower than those of patients without any meniscal tear, although with significant improvement in the amount of instability. Level of evidence was Level III.

Isolated meniscus injuries in skeletally immature children and adolescents: state of the art

The prevalence of isolated meniscal injuries in children and adolescents is low; however, we see an increase mainly due to intensified sports-related activities at an early age. A meniscal repair should be attempted whenever possible as children present with increased meniscal healing potential. The diagnosis and management of meniscal tears involve both patient factors and tear characteristics: size, anatomical location and associated injuries. Special attention should be given to the feature of discoid menisci and related tears as they require a specific management plan. This state-of-the-art review highlights the most recent studies on clinical evaluation, surgical techniques, tips and tricks, pitfalls, outcomes, return-to-sports, geographical differences and future perspectives related to meniscal injuries in children and adolescents.

Complex Meniscus Tears Treated with Collagen Matrix Wrapping and Bone Marrow Blood Injection: Clinical Effectiveness and Survivorship after a Minimum of 5 Years' Follow-Up

Purpose. To determine the 5-year success rate of the "all-inside" technique of arthroscopic meniscus suture and collagen membrane wrapping along with bone marrow blood injection, to evaluate the progression of degenerative changes and the impact of simultaneous anteriro cruciate ligament (ACL) reconstruction. Methods. Fifty-four consecutive patients with complex meniscal tears were treated with the previously described technique. The subjective scores (International Knee Documentation Committee 2000, Lysholm, EQ-5D-5L) and Barret clinical criteria of meniscal healing were recorded. Magnetic resonance images (MRIs) were assessed at 2 and 5 years postoperatively, using the Whole-Organ Magnetic Resonance Imaging Score (WORMS) criteria. Kaplan-Meier survival analyses were performed in order to assess the survivorship after the index procedure. Thirty-nine patients were divided into 2 groups: group A-isolated meniscus repair and group B-meniscus repair with concurrent ACL reconstruction. Results. Fifty-four patients were treated and 44 were available for analysis. There was a statistically significant improvement in subjective scores and clinical assessment between the preoperative, 2-year follow-up, and 5-year follow-up time points. EQ-5D-5L utility value was 0.9 ± 1 at final follow-up. The WORMS osteoarthritis severity grade had increased from 6.9 ± 5.0 points at the 2-year follow-up to 11.1 ± 9.6 points at the 5-year follow-up (P < 0.001). There was a significant difference between the groups after 60 months. The overall survival rate at final follow-up was 88%. Conclusions. The treatment option evaluated in this study has shown very good mid-term clinical and MRI-based outcomes as well as a favorable survival rate. Simultaneous ACL reconstruction is likely a factor for osteoarthritis progression.

Meniscal Injuries: Mechanism and Classification

Meniscal tears may be managed through conservative physical therapy and nonsteroidal anti-inflammatory medications or operative intervention. Meniscal repair is superior to partial meniscectomy with better functional outcomes and less severe degenerative changes over time. Surgical advances in operative techniques, modern instrumentation and biological enhancements collectively improve healing rates of meniscal repair. However, failed repair is not without consequences and can negative impact patient outcomes. Therefore, it is imperative for surgeons to have a thorough understanding of the vascular zones and biomechanical classifications of meniscal tears in order to best determine the most appropriate treatment.

Meniscus Repair Techniques

The menisci play a vital role in maintaining knee function and protecting the chondral surfaces. Acute and chronic tears are common injuries among both young athletes and older patients with early degenerative changes. The progression of physiological derangement and chondral injury after meniscus injury and meniscectomy have prompted interest in expanding meniscus repair techniques. Recent literature encourages an attempt at repair in tear patterns previously declared irreparable if the tissue quality allows. The orthopedic surgeon should understand the multitude of techniques available to them and be prepared to combine techniques to optimize the quality of their repair construct. While biological augmentation may show some promising early results, the quality of the current data precludes strong recommendations in their favor.

Degenerative Joint Disease After Meniscectomy

The meniscus has an important role in stabilizing the knee joint and protecting the articular cartilage from shear forces. Meniscus tears are common injuries and can disrupt these protective properties, leading to an increased risk of articular cartilage damage and eventual osteoarthritis. Certain tear patterns are often treated with arthroscopic partial meniscectomy, which can effectively relieve symptoms. However, removal of meniscal tissue can also diminish the ability of the meniscus to dissipate hoop stresses, resulting in altered biomechanics of the knee joint including increased contact pressures. This makes meniscal repair an important treatment consideration whenever possible. Understanding the incidence and mechanism of osteoarthritis development after arthroscopic partial meniscectomy as it relates to different tear morphologies and other treatment alternatives (ie, meniscus repair) is important to appropriately treat meniscus tears.

Mid-term evaluation of clinical and functional outcomes after arthroscopic medial longitudinal and bucket-handle meniscus repair

OBJECTIVES

The aim of this study was to evaluate clinical and functional outcomes following the arthroscopic medial meniscal repair.

PATIENTS AND METHODS

A total of 50 patients (42 males, 8 females; mean age: 32.9±7.6 years; range, 17 to 48 years) who underwent arthroscopic repair for longitudinal and bucket-handle medial meniscal tears between March 2005 and October 2011 were retrospectively evaluated. The patients were divided into two groups as those having a longitudinal tear (patient group, n=31) and having a bucket-handle tear (control group, n=19). Preoperative and final follow-up functional outcomes were evaluated using the Lysholm Knee Score (LKS), International Knee Documentation Committee (IKDC) score, Tegner Activity Scale (TAS) score, and Knee Injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

The mean follow-up was 61.7±22.8 (range, 36 to 110) months. The mean preoperative LKS, IKDC score, TAS, and KOOS scores were significantly improved at the final postoperative follow-up (p<0.05). There was no significant difference in functional outcome scores between longitudinal and bucket-handle repairs (p>0.05), and isolated repairs and concomitant meniscal repair and anterior cruciate ligament reconstruction (p>0.05).

CONCLUSION

Arthroscopic meniscal repair provides similar mid-term functional and clinical outcomes for longitudinal and bucket-handle medial meniscal tears. Concomitant meniscal repair does not seem to affect meniscal healing.

Excellent medium-term survival of an all-inside tensionable knotted suture device justifies repair of most meniscal tears encountered during reconstructive knee ligament surgery

PURPOSE

All-inside meniscal repair devices have evolved to allow surgeons to undertake complex repairs in a timely and efficient manner. This is advantageous in active patients, where meniscus preservation is critical in preserving joint function and stability. The aim of the study was to evaluate the failure rate of all-inside meniscal repair performed in patients undergoing reconstructive ligament surgery using a particular meniscal repair device.

METHODS

Patients were identified using a single-site prospectively maintained patient registry. Primary outcome was failure, defined as return to surgery with documented failure of repair. Complication rates and functional scores were also recorded. Patients in whom meniscal repair failure was identified were further assessed, to identify any common features.

RESULTS

Over an 8-year period, 323 patients underwent meniscal repair at the time of ligament reconstruction, compared to 244 meniscectomies. Of these, 286 patients underwent repair using an all-inside suture device. One-hundred and twenty-seven repairs were to the medial meniscus only, 124 were lateral, and in 35 patients both menisci were repaired. Follow-up was to a median of 51.5 months. There were 31 (9.7%) failures reported at a median of 22 months post-operatively (IQR 13.5-41.5). Medial repair failures were seen more frequently than lateral (13.6% versus 5.6% OR 2.62 95% CI 1.17-5.88 p = 0.022). Failure of ACL reconstruction was associated with meniscal repair failure (OR 5.83 95% CI 1.55-21.95 p = 0.0039). Multi-ligament reconstruction was undertaken in 70/286 patients receiving meniscal repair and was not associated with failure (OR 1.3 95% CI 0.57-2.98 p = 0.51). Mode number of all-inside sutures used was 3 in both medial and lateral repairs (Range 1-9 lateral; 1-7 medial).

CONCLUSIONS

All-inside repair is a safe and versatile technique which can be used in the majority of meniscal tears encountered during ligament reconstruction with excellent mid-term success. Failure is seen more commonly in medial sided repairs and with failure of ACL reconstruction.

LEVEL OF EVIDENCE

IV.

Meniscal pathology in children and adolescents

The menisci play a key role in knee biomechanics and long-term cartilage protection. Preserving the meniscus is thus a major functional consideration in children and adolescents. In normal menisci, lesions are traumatic in origin. They are often vertical, in the posterior segment, associated with anterior cruciate ligament tear. In abnormal menisci, lesions are much more specific to children, occurring atraumatically, mainly in discoid menisci. Clinical signs of traumatic meniscal lesion are minimal, and associated ligament involvement should be systematically screened for. In contrast, clinical findings are rich and specific in discoid malformative pathology, sometimes showing the typical "clunk" sign highly suggestive of a detachment. The complementary examination of choice is MRI. In children more than in adults, lesions need screening for in apparently normal menisci. This particularly concerns ramp lesions of the medial meniscus. It is important also to be aware of false signs, and notably linear hypersignal of vascular origin in the posterior segment of the medial meniscus. MRI is essential in determining type of tear and guiding surgery in discoid meniscal pathology. Indications for meniscal repair in children are maximal, even in lesions extending into the white zone, and the risk of failure needs to be assumed. All meniscal suture techniques - all-inside, in-out and out-in - need to be acquired. Meniscectomy, even partial, should be exceptional. Treatment of symptomatic discoid meniscus usually involves minimal central meniscoplasty and suture of the discovered lesion. Results of meniscal repair in children are generally very satisfactory, whatever the type or site of lesion. Vertical suture is to be preferred; suture failure is often only partial. In all, optimal treatment of meniscal pathology in children and adolescents requires perfect knowledge of pediatric specificities and above all mastery of repair techniques to restore meniscal tissue as fully as possible so as to conserve future knee function.

Incidence of Medial and Lateral Meniscal Tears After Delayed Anterior Cruciate Ligament Reconstruction in Pediatric Patients

Background:

The treatment of pediatric anterior cruciate ligament (ACL) injuries is controversial, and no clear management guidelines have been established.

Purpose:

To evaluate the association between elapsed time from ACL injury to surgery and the incidence of meniscal tears and chondral injuries in patients aged ≤16 years.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Between December 2012 and April 2019, a total of 207 consecutive knees in 207 patients aged ≤16 years underwent primary ACL reconstruction and were included in this study. Patients were divided into 1 of 2 groups (early group [≤150 days] and delayed group [>150 days]) based on the time between injury and surgery. Patient records, including arthroscopic findings identified by 2 experienced knee surgeons at the time of surgery, were reviewed for demographic information, incidence and types of medial and lateral meniscal tears, and chondral injuries and their locations in each group.

Results:

There were 180 knees in the early group and 27 knees in the delayed group. The delayed group showed a significantly higher rate of medial meniscal tears than the early group: 16 of 27 (59.2%) and 46 of 180 (25.6%), respectively (odds ratio [OR], 4.24 [95% CI, 1.83-9.33]; P = .0011). The delayed group had a significantly lower rate of lateral meniscal tears than the early group: 6 of 27 (22.2%) and 90 of 180 (50.0%), respectively (OR, 0.29 [95% CI, 0.11-0.70]; P = .007). The delayed group had significantly higher rates of chondral injuries in the medial femoral condyle and the medial tibial plateau than the early group: 8 of 27 (29.6%) and 25 of 180 (13.9%), respectively (OR, 2.61 [95% CI, 1.03-6.62]; P = .049), and 2 of 27 (7.4%) and 1 of 180 (0.6%), respectively (OR, 14.32 [95% CI, 1.58-208.10]; P = .045).

Conclusion:

Delayed ACL reconstruction was associated with an increased incidence of medial chondral injuries and medial meniscal tears but with a decreased incidence of lateral meniscal tears.

Arthroscopic repair of horizontal cleavage meniscus tears provides good clinical outcomes in spite of poor meniscus healing

PURPOSE

The purpose of this study was to evaluate the clinical outcomes and meniscus healing after arthroscopic repair of horizontal-cleavage meniscus tears, compared with vertical-longitudinal meniscus tears.

METHODS

This was a retrospective review of a consecutive series of 52 meniscal repairs for horizontal-cleavage tears (n = 27) or vertical-longitudinal tears (n = 25); the groups were compared with respect to clinical symptoms and meniscal healing. Arthroscopic meniscal repair was performed using the inside-out technique with a marrow-stimulating technique. Clinical symptoms were evaluated using the Lysholm score and Knee injury and osteoarthritis outcome score (KOOS). Meniscus healing was evaluated by MRI.

RESULTS

The mean follow-up periods were 35.4 ± 8.9 months in the horizontal-cleavage tear group and 39.8 ± 8.3 months in the vertical-longitudinal tear group. There were no significant differences in Lysholm score and KOOS, including each subscale, between the horizontal-cleavage tear- and vertical-longitudinal tear-groups at the final follow-up. At the final follow-up, MRI meniscus grades 0 and 1 were significantly more frequent in the vertical-longitudinal tear-group than in the horizontal-cleavage tear-group, while grade 3 was significantly more frequent in the horizontal-cleavage tear group than in the vertical-longitudinal tear group (p < 0.0001).

CONCLUSIONS

Although meniscus healing of horizontal-cleavage tears may be poor, arthroscopic repair should be considered for horizontal-cleavage tears because it does provide good clinical outcomes.

LEVEL OF EVIDENCE

IV.

Meniscus repairs in the adolescent population-safe and reliable outcomes: a systematic review

PURPOSE

The purpose of this study was to determine the outcomes of meniscus repair in the adolescent population, including: (1) failure and reoperation rates, (2) clinical and functional results, and (3) activity-related outcomes including return to sport.

METHODS

Two authors independently searched MEDLINE, Cochrane Central Register of Controlled Trials & Cochrane Library, and CINHAL databases for literature related to meniscus repair in an adolescent population according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. No meta-analysis was performed in this qualitative systematic review.

RESULTS

Thirteen studies, including no Level I, one Level II, one Level III, and eleven Level IV studies yielded 466 patients with 503 meniscus repairs. All defined meniscal re-tear as a primary endpoint, with a reported failure rate ranging from 0 to 42% at a follow-up ranging from 22 to 211 months. There were a total of 93 failed repairs. IKDC scores were reported in four studies with a mean improvement ranging from 24 to 42 (P < 0.001). Mean post-operative Lysholm scores were reported in seven studies, ranging from 85 to 96. Additionally, four of those studies provided mean pre-operative Lysholm scores, ranging from 56 to 79, with statistically significant mean score improvements ranging from 17 to 31. Mean post-operative Tegner Activity scores were reported in nine studies, with mean values ranging from 6.2 to 8.

CONCLUSION

This systematic review demonstrates that both subjective and clinical outcomes, including failure rate, Lysholm, IKDC, and Tegner activity scale scores, are good to excellent following meniscal repair in the adolescent population. Further investigations should aim to isolate tear type, location, surgical technique, concomitant procedures, and rehabilitation protocols to overall rate of failure and clinical and functional outcomes.

LEVEL OF EVIDENCE

IV.

Microvascular Anatomy and Intrinsic Gene Expression of Menisci From Young Adults

BACKGROUND

Meniscal vascular supply is an important determinant of its healing potential. It has been reported that only the peripheral 30% of the meniscus is vascularized in cadavers aged 53 to 94 years; however, the vascularity in young patients, in whom meniscal repair is more often performed, is unknown.

PURPOSE

The primary objective was to analyze and measure the microvascular anatomy of the meniscus in adult cadaveric specimens <35 years old. The secondary objective was to assess angiogenic potential by quantifying regional gene expression in a meniscal allograft cohort <45 years old.

STUDY DESIGN

Descriptive laboratory study.

METHODS

In part 1 of this study, 13 fresh-frozen cadaveric knees (age range, 22-34 years; mean, 28.5 years) underwent popliteal artery India ink injection and tissue clearing using a Spalteholz technique, followed by microvascular vascular measurement. In part 2, mRNA was isolated from 13 meniscal allografts (age range, 17-43 years; mean, 27.2 years), and expression of angiogenic genes, vascular endothelial growth factor (VEGF), and vascular endothelial growth factor receptor 1 (FLT1) was quantified using real-time polymerase chain reaction.

RESULTS

The maximal depth of vascular penetration into the periphery of the medial and lateral menisci ranged from 0% to 42% and 0% to 48%, respectively. There was variation in the degree of vascular penetration within the medial meniscus, with the posterior horn having a significantly smaller depth of penetration (median, 8.7%) than that of the anterior horn (median, 17.4%; P < .0001) or midbody (median, 17.5%; P = .0003). There were no differences in angiogenesis gene expression (VEGF/FLT1) based on circumferential or radial meniscal locations.

CONCLUSION

The vascular supply of the medial and lateral menisci in specimens from adults <35 years of age extended farther than what was reported in specimens from older individuals; however, median values remained consistent. Gene expression of the angiogenic marker VEGF was low throughout all regions of uninjured menisci from young adults, which is consistent with reports in older specimens.

CLINICAL RELEVANCE

Improved understanding of meniscal vascular supply in young adults is critical to informing clinical treatment decisions.

Molecular biology of meniscus pathology: Lessons learned from translational studies and mouse models

Injury to any individual structure in the knee interrupts the overall function of the joint and initiates a cascade of biological and biomechanical changes whose endpoint is often osteoarthritis (OA). The knee meniscus is an integral component of knee biomechanics and may also contribute to the biological homeostasis of the joint. Meniscus injury altering knee function is associated with a high risk of OA progression, and may also be involved in the initiation of OA. As the relationship between meniscus injury and OA is very complex; despite the availability of transcript level data on human meniscus injury and meniscus mediated OA, mechanistic studies are lacking, and available human data are difficult to validate in the absence of patient-matched noninjured control tissues. As similarities exist between human and mouse knee joint structure and function, investigators have begun to use cutting-edge genetic and genomic tools to examine the usefulness of the mouse as a model to study the intricate relationship between meniscus injury and OA. In this review, we use evidence from human meniscus research to identify critical barriers hampering our understanding of meniscus injury induced OA and discuss strategies to overcome these barriers, including those that can be examined in a mouse model of injury-mediated OA.

Risk of Subsequent Knee Arthroplasty After Sports Medicine Procedures

INTRODUCTION

Approximately 10% of men and 13% of women older than the age of 60 are affected by symptomatic osteoarthritis of the knee. Anatomic repair or reconstruction after knee injury has been a central tenet of surgical treatment to reduce the risk of osteoarthritis. The purpose of this study was to examine common sports medicine procedures of the knee and determine the proportion of patients who subsequently undergo total knee arthroplasty (TKA).

METHODS

The MarketScan database was queried from the period of January 2007 through December 2016. Patients were identified, who underwent a procedure of the knee, as defined by Current Procedural Terminology codes relating to nonarthroplasty procedures of the knee. Patients in whom laterality could not be confirmed or underwent another ipsilateral knee procedure before TKA were excluded from this study. The primary outcome of this study was the overall rate of TKA after index knee surgery. Time from index procedure to TKA was a secondary outcome. A multivariate regression analysis was used to control for covariates such as age, sex, and comorbidity status.

RESULTS

A total of 843,749 patients underwent one of the 13 common sports medicine procedures of the knee. The procedure with the highest unadjusted rate of subsequent TKA was arthroscopic osteochondral allograft (5.81%), whereas anterior cruciate ligament (ACL) reconstruction with meniscus repair demonstrated the lowest rate of subsequent TKA (0.01%). When adjusting for confounding factors, the regression analysis identified meniscal transplantation (odds ratio [OR] = 3.06, P < 0.0001) as having the highest risk of subsequent TKA, followed by osteochondral autograft (OR = 1.74, P = 0.0424) and arthroscopic osteochondral allograft (OR = 1.49, P < 0.0001). ACL reconstruction with meniscus repair (OR = 0.02, P < 0.0001), ACL reconstruction alone (OR = 0.17, P < 0.0001), ACL with meniscectomy (OR = 0.20, P < 0.0001), and meniscal repair (OR = 0.65, P < 0.0001) had the lowest rate of subsequent TKA. ACL reconstruction with meniscus repair had the longest period from index procedure to TKA at 2827 days.

CONCLUSION

ACL reconstruction and meniscus preservation demonstrated an extremely low rate of conversion to TKA when compared with patients who needed salvage interventions such as meniscus and cartilage transplantation. None of the salvage interventions delayed the need for a TKA. Meniscal transplantation had the highest risk of all procedures of going on to a TKA.

Meniscal Repair Techniques

The menisci play a vital role in knee joint stability, load distribution, and lubrication, protecting the joint surfaces from degenerative change. Meniscal repair protects the joint from increased loading and when successful reduces progression of osteoarthritis. Successful repair involves accurate surgical techniques, guarded postoperative rehabilitation, and potential use of additional biologics to promote healing. An integrated approach to meniscal surgery is required as part of an overall strategy to preserve and restore knee function, preserving meniscal tissue whenever possible. This article reviews the repair techniques: procedures, indications, and rehabilitation for meniscal repair.

Management of traumatic meniscus tears: the 2019 ESSKA meniscus consensus

PURPOSE

The importance of meniscus integrity in the prevention of early osteoarthritis is well known, and preservation is accepted as the primary goal. The purpose of the ESSKA (European Society for Sports Traumatology, Knee Surgery and Arthroscopy) European consensus on traumatic meniscus tears was to provide recommendations for the treatment of meniscus tears based on both scientific evidence and the clinical experience of knee experts.

METHODS

Three groups of surgeons and scientists elaborated and ratified the so-called formal consensus process to define the recommendations for the management of traumatic meniscus tears. A traumatic meniscus tear was defined as a tear with an acute onset of symptoms caused by a sufficient trauma. The expert groups included a steering group of eight European surgeons and scientists, a rating group of another nineteen European surgeons, and a peer review group. The steering group prepared twenty-seven question and answer sets based on the scientific literature. The quality of the answers received grades of A (a high level of scientific support), B (scientific presumption), C (a low level of scientific support) or D (expert opinion). These question and answer sets were then submitted to and evaluated by the rating group. All answers were scored from 1 (= totally inappropriate) to 9 (= totally appropriate) points. Thereafter, the comments of the members of the rating group were incorporated by the steering group and the consensus was submitted to the rating group a second time. Once a general consensus was reached between the steering and rating groups, the finalized question and answer sets were submitted for final review by the peer review group composed of representatives of the ESSKA-affiliated national societies. Eighteen representatives replied.

RESULTS

The review of the literature revealed a rather low scientific quality of studies examining the treatment of traumatic meniscus tears. Of the 27 questions, only one question received a grade of A (a high level of scientific support), and another received a grade of B (scientific presumption). The remaining questions received grades of C and D. The mean rating of all questions by the rating group was 8.2 (95% confidence interval 8.1-8.4). A general agreement that MRI should be performed on a systematic basis was not achieved. However, MRI was recommended when arthroscopy would be considered to identify concomitant pathologies. In this case, the indication for MRI should be determined by a musculoskeletal specialist. Based on our data, stable left in situ lateral meniscus tears appear to show a better prognosis than medial tears. When repair is required, surgery should be performed as early as possible. Evidence that biological enhancement such as needling or the application of platelet-rich plasma would improve healing was not identified. Preservation of the meniscus should be considered as the first line of treatment because of an inferior clinical and radiological long-term outcome after partial meniscectomy compared to meniscus repair.

DISCUSSION

The consensus was generated to present the best possible recommendations for the treatment of traumatic meniscus tears and provides some groundwork for a clinical decision-making process regarding the treatment of meniscus tears. Preservation of the meniscus should be the first line of treatment when possible, because the clinical and radiological long-term outcomes are worse after partial meniscectomy than after meniscus preservation. The consensus clearly states that numerous meniscus tears that were considered irreparable should be repaired, e.g., older tears, tears in obese patients, long tears, etc. LEVEL OF EVIDENCE: II.

Arthroscopically Repaired Bucket-Handle Meniscus Tears: Patient Demographics, Postoperative Outcomes, and a Comparison of Success and Failure Cases

OBJECTIVE

To define patient demographics, preoperative, and intraoperative surgical variables associated with successful or failed repair of bucket-handle meniscal tears.

DESIGN

All patients who underwent arthroscopic repair of a bucket-handle meniscus tear at a single institution between May 2011 and July 2016 with minimum 6-month follow-up were retrospectively identified. Patient demographic, preoperative (including imaging), and operative variables were collected and evaluated. A Kaplan-Meier curve was generated to demonstrate meniscus repair survivorship.

RESULTS

In total, 75 patients (78 knees) with an average age of 26.53 ± 10.67 years met inclusion criteria. The average follow-up was 23.41 ± 16.43 months. Fifteen knees (19.2%) suffered re-tear of the repaired meniscus at an average 12.24 ± 9.50 months postoperatively. Survival analysis demonstrated 93.6% survival at 6 months, 84.6% survival at 1 year, 78.4% survival at 2 years, and 69.9% survival at 3 years. There was significant improvement from baseline to time of final follow-up in all patient-reported outcome (P < 0.05) except Marx score (P = 0.933) and SF-12 Mental Subscale (P = 0.807). The absence of other knee pathology (including ligament tear, contralateral compartment meniscal tear, or cartilage lesions) noted intraoperatively was the only variable significantly associated with repair failure (P = 0.024). Concurrent anterior cruciate ligament reconstruction (vs. no concurrent anterior cruciate ligament reconstruction) trended toward significance (P = 0.059) as a factor associated with successful repair.

CONCLUSIONS

With the exception of the absence of other knee pathology (including ligament tear, contralateral compartment meniscal tear, or cartilage lesions) noted intraoperatively, no other variables were significantly associated with re-tear. The results are relatively durable with 84.6% survival at 1 year. Surgeons should attempt meniscal repair when presented with a bucket-handle tear.

Epidemiology, Injury Patterns, and Treatment of Meniscal Tears in Pediatric Patients: A 16-Year Experience of a Single Center

Background:

Meniscal injuries in children continue to increase, which may be attributable to increasing levels of athletic participation and may be associated with additional injuries or need for additional surgeries.

Purpose:

To better understand the patterns of pediatric meniscal injuries by analyzing tear location, morphologic features, and associated injury patterns over a 16-year period.

Study Design:

Case series; Level of evidence, 4.

Methods:

Pediatric patients were identified and were included in the study if age at the time of initial surgery for meniscal tear was between 5 and 14 years for female patients and 5 and 16 years for male patients. Patients were observed until age 18, and any subsequent surgeries were noted. Demographic factors, tear type and location, associated injuries, and treatment type were analyzed.

Results:

Mean patient age at surgery was 13.3 years, and 37% of patients were female. A total of 1040 arthroscopic meniscal surgeries in 880 pediatric patients were evaluated. There were 160 reoperations in 138 patients, representing a reoperation rate of 15%. These included 98 reoperations on the ipsilateral knee in 88 patients and 62 operations for injuries to the contralateral knee in 50 patients; 53% of surgeries were meniscal repair, as opposed to partial meniscectomy, and the most common technique was an all-inside repair (91%). Significant differences were identified between male and female patients. Male patients were more likely to have lateral meniscus (74% vs 65%), posterior horn (71% vs 60%), peripheral (45% vs 30%), and vertical tears (31% vs 21%); concomitant ACL injury (50% vs 40%); and an associated osteochondritis dissecans lesion (7% vs 4%). Female patients were more likely to have medial meniscus (24% vs 17%), anterior horn (25% vs 15%), and degenerative tears (34% vs 26%); discoid meniscus (33% vs 24%); and isolated meniscal tears (47% vs 33%).

Conclusion:

This evaluation of a large series of patients has helped characterize injury patterns associated with pediatric meniscal surgeries. Most meniscal tears were repaired (53%) and were associated with additional injuries (62%), especially anterior cruciate ligament injuries (48%). More than 25% of patients had a discoid meniscus. Injury patterns differed significantly between male and female patients.

Meniscal Repairs in the Adolescent Knee: Can the Number of Fixation Sites Improve Outcomes?

Background:

Meniscal pathology in children and adolescents is now a common occurrence because of their ever-increasing participation in youth sports.

Purpose:

To investigate the outcomes of arthroscopic meniscal repair in an adolescent cohort and analyze the variables that may affect outcomes, specifically the number of fixation sites utilized during repair.

Study Design:

Case series; Level of evidence, 4.

Methods:

A retrospective review of all children and adolescents younger than 18 years who underwent arthroscopic meniscal repair at a single institution was performed. Patient characteristics, operative details (eg, tear pattern, tear location, method of repair, and number of fixation sites [determined based on the number of sutures used for repair]), and concomitant procedures were recorded.

Results:

A total of 175 primary meniscal repairs met inclusion criteria and were analyzed. Of this cohort, 115 were able to be contacted and were included in the final study cohort. The mean follow-up was 41 months. The mean age of the children was 14.9 years, and 91 (79%) had concomitant anterior cruciate ligament reconstructions with their meniscal repair. The mean Pediatric International Knee Documentation Committee functional outcome score was 91 (range, 43-100), and the mean Lysholm functional outcome score was 91 (range, 47-100). Of the 115 meniscal repairs, there were a total of 19 reoperations (17%); 15 (13%) were because of meniscal repair failures. The only variable that statistically increased the risk of meniscal repair failure was low number of fixation sites, with the failure group having a mean of 1.79 sutures and the nonfailure group having a mean of 2.97 sutures (P = .03).

Conclusion:

Successful meniscal repairs and a lower failure rate may be achieved with a greater number of fixation sites with promising results at a minimum 2-year follow-up. Validated functional outcome scores were good, with a 13% failure rate. Larger cohort, longer term, multicenter multisurgeon data are still needed to further elucidate the number of fixation sites needed when performing a meniscal repair in the pediatric and adolescent knee.

Degenerative changes in cartilage likely occur in the medial compartment after anterior cruciate ligament reconstruction

PURPOSE

Magnetic resonance imaging with T1ρ mapping is used to quantify the amount of glycosaminoglycan in articular cartilage, which reflects early degenerative changes. The purposes of this study were to evaluate early degenerative changes in knees after anterior cruciate ligament (ACL) reconstruction by comparing T1ρ values before and 2 years after surgery and investigate whether surgical factors and clinical outcomes are related to differences in T1ρ values.

METHODS

Fifty patients who underwent unilateral primary ACL reconstruction were evaluated using T1ρ mapping before and 2 years after surgery. Three regions of interest (ROIs) were defined in the cartilage associated with the medial (M) and lateral (L) weight-bearing areas of the femoral condyle (FC) (anterior: MFC1 and LFC1, middle: MFC2 and LFC2, and posterior: MFC3 and LFC3). Two ROIs associated with the tibial plateau (T) were defined (anterior: MT1 and LT1, and posterior: MT2 and LT2). T1ρ values within the ROIs were measured before and 2 years after surgery and compared using the paired t test. Correlations between the difference in T1ρ values at these two time points and patient characteristics, presence of a cartilaginous lesion, graft type, and postoperative anteroposterior laxity were also evaluated using Pearson's and Spearman's correlation coefficients.

RESULTS

There was a significant increase in T1ρ before versus 2 years after surgery in the MT1, MT2, LFC1, and LT1 areas, and a significant decrease in the LFC3 and LT2 areas. There was a significant correlation between postoperative anterior-posterior laxity and a postoperative increase in T1ρ values in the MFC3 (r = 0.37, P = 0.013) and MT2 (r = 0.35, P = 0.021) areas. Increases in T1ρ values in the MFC2 area were negatively correlated with KOOS symptoms (ρ = - 0.349, P = 0.027) and quality of life (ρ = - 0.374, P = 0.017) subscale scores.

CONCLUSION

Early degenerative changes in medial articular cartilage were observed with T1ρ mapping at 2 years after ACL reconstruction. Postoperative anterior-posterior laxity is correlated with an increase in T1ρ values in the posteromedial femur and tibia. An increase in T1ρ values in the central medial femoral condyle was associated with knee symptoms.

LEVEL OF EVIDENCE

III.

Clinical Outcomes of Inside-Out Meniscal Repair According to Anatomic Zone of the Meniscal Tear

Background

There is significant discrepancy in the reported vascularity within the meniscus, and a progressively diminishing blood supply may indicate a differential healing capacity of tears that is dependent on the affected meniscal zone.

Purpose

To examine the outcomes after inside-out meniscal repair in all 3 meniscal vascularity zones.

Study Design

Cohort study; Level of evidence, 3.

Methods

Patients were included if they underwent inside-out meniscal repair by a single surgeon between 2010 and 2014 and had a minimum 2-year follow-up. Patients were divided into 3 groups based on the meniscal tear location (red-red, red-white, and white-white zones) as determined during an intraoperative assessment. Patient-reported outcome scores were obtained at final follow-up.

Results

A total of 173 patients (mean age, 33.6 ± 14.3 years) were included, with a mean follow-up of 2.9 ± 0.9 years. All patients demonstrated significant improvements with inside-out meniscal repair from preoperatively to postoperatively, regardless of the meniscal tear location. Patients who underwent meniscal repair in the red-red and red-white zones had significantly increased postoperative Tegner, Lysholm, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores compared with patients who underwent meniscal repair in the white-white zone (P < .05). Patients who underwent acute repair (≤6 weeks) demonstrated significantly higher improvements on the Tegner activity scale (acute: 5.8 ± 2.2; chronic: 4.6 ± 2.2; P = .001) and Lysholm score (acute: 85.6 ± 13.3; chronic: 80.8 ± 13.5; P = .025) compared with patients treated beyond 6 weeks from injury, regardless of the meniscal tear zone. Patients with grade IV femoral condyle chondral lesions at the time of surgery had significantly inferior outcomes compared with patients with grade I through III chondral lesions, regardless of the meniscal tear zone. Three patients (1.7%) subsequently underwent revision inside-out repair, and 3 (1.7%) underwent partial meniscectomy.

Conclusion

Patients who underwent inside-out meniscal repair demonstrated significant improvements on subjective outcome measures at a minimum 2-year follow-up, regardless of the meniscal tear zone. Inside-out meniscal repair is recommended for potentially reparable meniscal tears in all 3 vascular zones; however, improved outcomes can be achieved when performed acutely, in the absence of full-thickness femoral condyle chondral injuries, and in the red-red and red-white zones.

Evaluation of Midterm Clinical and Radiographic Outcomes of Arthroscopically Repaired Vertical Longitudinal and Bucket-Handle Lateral Meniscal Tears

Background:

Lateral meniscal tears in the stable knee are rare. There are few comparative studies evaluating functional and radiological outcomes of vertical longitudinal and bucket-handle lateral meniscal tears.

Purpose:

To evaluate the midterm clinical and radiological outcomes of arthroscopically repaired traumatic vertical longitudinal and bucket-handle lateral meniscal tears.

Study Design:

Case series; Level of evidence, 4.

Methods:

A total of 43 full-thickness lateral meniscal repairs, including 22 (51.2%) for vertical longitudinal tears and 21 (48.8%) for bucket-handle tears, were evaluated. A clinical assessment was performed according to the Barrett criteria, and patient outcomes were measured with the Lysholm knee score, Tegner activity scale, and overall satisfaction scale. Magnetic resonance imaging was used as the radiological re-examination method preoperatively and at final follow-up. A subgroup analysis examining isolated repair versus repair with concurrent anterior cruciate ligament (ACL) reconstruction was performed.

Results:

The mean follow-up period was 63.2 months (range, 24-86 months). Based on clinical and radiological outcomes, 38 of the 43 repairs (88.3%) were successful, and the remaining 5 (11.6%) cases were considered to be failures. Overall, the combined results for both groups demonstrated an improvement in the Lysholm score, Tegner score, and patient satisfaction. There was no significant difference in the postoperative Lysholm score (91.4 vs 87.0, respectively; P = .223), Tegner score (5.4 vs 5.5, respectively; P = .872), or patient satisfaction (7.2 vs 7.4, respectively; P = .624) between bucket-handle repair and vertical longitudinal repair. The subgroup analysis demonstrated no difference in outcome scores for isolated repair versus repair with concurrent ACL reconstruction. Smoking was identified as a risk factor for repair failure.

Conclusion:

Comparable clinical and radiological outcomes were obtained after vertical longitudinal and bucket-handle lateral meniscal repairs using the all-inside or hybrid suture technique with different suture configurations, regardless of whether ACL reconstruction was performed. Smoking was identified as a risk factor for failure.

Outcomes After the Operative Treatment of Bucket-Handle Meniscal Tears in Children and Adolescents

Background:

Bucket-handle meniscal tears (BHMTs), which we define as vertical longitudinal tears of the meniscus with displacement of the torn inner fragment toward the intercondylar notch region, are a well-recognized tear pattern. Optimizing the management of BHMTs in younger patients is important, as preserving meniscal tissue may limit future joint degeneration.

Purpose/Hypothesis:

The purpose of this study was to review the patient demographics, clinical presentation, operative details, outcomes, and risk factors for a reoperation associated with operatively treated BHMTs in a pediatric population. We hypothesized that the repair of BHMTs in adolescents would yield a higher reoperation rate than meniscectomy in our population.

Study Design:

Case-series; Level of evidence, 4.

Methods:

A departmental database was queried to identify all patients 19 years or younger who presented with a BHMT and underwent surgery between October 2002 and February 2013. Clinical, radiological, and surgical data were retrospectively collected, and risk factors for a reoperation and persistent pain were assessed in all patients with longer than or equal to 6 months of follow-up.

Results:

A total of 280 BHMTs were treated arthroscopically by 1 of 8 sports medicine fellowship–trained surgeons. The mean age at surgery was 15.5 ± 2.5 years (range, 2.1-19.2 years), and most patients were male (177/280; 63%). Most injuries occurred during sports (203/248; 82%) and involved the medial meniscus (157/280; 56%). Concurrent anterior cruciate ligament (ACL) surgery was performed in 103 cases (37%). Meniscal repair was performed in 181 cases (65%) and was more common in younger patients (P = .01) and for the lateral meniscus (P < .001). Among 185 (66%) cases with longer than or equal to 6 months of adequate follow-up data (which included 126 meniscal repairs [68%]), a meniscus-related reoperation occurred in 45 (24%) cases. A reoperation related to the original BHMT injury or surgery was more common after meniscal repair than after meniscectomy (40/126 [32%] vs 5/59 [8%], respectively) (P = .001) and less common with concurrent ACL surgery (P = .07), although this was not statistically significant. Among patients injured during sports and with adequate follow-up, all but 1 patient (176/177; 99%) returned to sports; a slower rate of return was seen in those undergoing meniscal repair (P = .002) and concurrent ACL surgery (P < .001). At final follow-up, 170 of 185 patients (92%) were pain free. For the 15 patients with persistent pain at final follow-up, no identifiable risk factors for persistent pain were identified.

Conclusion:

Most BHMTs in younger patients occurred in males and during sports and affected the medial meniscus. Concurrent ACL surgery was indicated in approximately one-third of cases and was associated with a lower reoperation rate and slower return to sports. Two-thirds of patients underwent meniscal repair, over two-thirds of whom did not require a reoperation during the study period, despite the high activity levels in this age group.

Posterior Horn Repair Augmented With the Central Portion of Thickened Meniscus for Large Posterolateral Corner Loss Type of Discoid Lateral Meniscus

Large posterolateral corner loss type of discoid lateral meniscus tear is unsalvageable. Therefore, subtotal meniscectomy has been the only treatment option in this case. However, long-term results of subtotal or total meniscectomy have shown a high prevalence of early degenerative changes. Persistent symptoms, such as increased pain, snapping, giving way, locking, and limited extension, can be attributed to progressive loss of posterior tibial meniscal attachment and meniscal degeneration, especially in the posterior horn. The purpose of this technique-based article is to describe a partial repair, posterior horn repair augmented with the central portion of the discoid lateral meniscus that would have been removed if a subtotal meniscectomy were performed and bone marrow stimulation in the intercondylar notch to improve meniscal healing.

Earlier anterior cruciate ligament reconstruction is associated with a decreased risk of medial meniscal and articular cartilage damage in children and adolescents: a systematic review and meta-analysis

PURPOSE

To evaluate the association between surgical timing and the incidence of secondary meniscal or chondral damage in children and adolescents with anterior cruciate ligament (ACL) ruptures.

METHODS

Three electronic databases, PubMed, MEDLINE, and EMBASE, were systematically searched from database inception until October 16, 2017 by two reviewers independently and in duplicate. The inclusion criteria were English language studies that reported the incidence of meniscal and articular cartilage damage in children or adolescent athletes with ACL injuries as well as the timing of their ACL reconstruction (ACLR). Risk ratios were combined in a meta-analysis using a random effects model.

RESULTS

A total of nine studies including 1353 children and adolescents met the inclusion criteria. The mean age of patients included was 14.2 years (range 6-19), and 45% were female. There was a significantly decreased risk of concomitant medial meniscal injury in those reconstructed early (26%) compared to those with delayed reconstruction (47%) [pooled risk ratio (RR) = 0.49, 95% CI 0.36-0.65, p < 0.00001]. There was also a significantly reduced risk of medial femoral chondral (RR = 0.48, 95% CI 0.31-0.75, p = 0.001), lateral femoral chondral (RR = 0.38, 95% CI 0.20-0.75, p = 0.005), tibial chondral (RR = 0.45, 95% CI 0.27-0.75, p = 0.002), and patellofemoral chondral (RR = 0.41, 95% CI 0.20-0.82, p = 0.01) damage in the early reconstruction group in comparison to the delayed group.

CONCLUSION

Pooled results from observational studies suggest that early ACLR results in a significantly decreased risk of secondary medial meniscal injury, as well as secondary medial, lateral, and patellofemoral compartment chondral damage in children and adolescents. This study provides clinicians with valuable information regarding the benefits of early ACL reconstruction in children and adolescents, and can be used in the decision making for athletes in this population.

LEVEL OF EVIDENCE

IV.

Seventeen-Year Follow-up After Meniscal Repair With Concomitant Anterior Cruciate Ligament Reconstruction in a Pediatric and Adolescent Population

BACKGROUND

Studies have shown good and excellent clinical and radiographic results after meniscal repair. Limited published information exists on the long-term outcomes, however, especially in a pediatric and adolescent population.

PURPOSE

To determine long-term results of meniscal repair and concomitant anterior cruciate ligament (ACL) reconstruction in a pediatric and adolescent population. Specifically, the aims were to determine the clinical success rate of meniscal repair with concomitant ACL reconstruction, compare results with midterm outcomes, and analyze risk factors for failure.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Cases of meniscal repair with concomitant ACL reconstruction between 1990 and 2005 were reviewed among patients aged ≤18 years. Patient demographics, injury history, and surgical details were recorded, and risk factors for failure were analyzed. Physical examination findings and clinical outcomes at latest available follow-up were collected. Subjective knee outcomes were compared with midterm results. Descriptive statistics and univariate analysis were used to evaluate the available data.

RESULTS

Forty-seven patients (30 females, 17 males) with a mean age of 16 years (SD, 1.37) and a mean follow-up of 16.6 years (SD, 3.57) were included in this study. Overall, 13 patients (28%) failed meniscal repair and required repeat surgery at the time of final follow-up. Of the 13 failures, 9 underwent a subsequent meniscectomy; 2, meniscectomy and revision ACL reconstruction; 1, meniscal repair and revision ACL reconstruction; and 1, meniscal repair and subsequent meniscectomy. Mean International Knee Documentation Committee scores improved from 47.9 preoperatively to 87.7 postoperatively ( P < .01), and the mean score at long-term follow-up (87.7) did not significantly differ from that at the midterm follow-up (88.5) at a mean 7.4 years ( P = .97). Mean Tegner Activity Scale scores improved from 1.9 preoperatively to 6.3 postoperatively ( P < .01) and decreased from 8.3 at preinjury to 6.3 at final long-term follow-up ( P < .01).

CONCLUSION

In conclusion, the long-term overall clinical success rate (failure-free survival) was 72% for repair of pediatric and adolescent meniscal tears in the setting of concomitant ACL reconstruction. Patients reported excellent knee subjective outcome scores that remained favorable when compared with midterm follow-up.

Arthroscopic repair of the meniscus: Surgical management and clinical outcomes

From the biomechanical and biological points of view, an arthroscopic meniscal repair (AMR) should always be considered as an option. However, AMR has a higher reoperation rate compared with arthroscopic partial meniscectomy, so it should be carefully indicated.

Compared with meniscectomy, AMR outcomes are better and the incidence of osteoarthritis is lower when it is well indicated.

Factors influencing healing and satisfactory results must be carefully evaluated before indicating an AMR.

Tears in the peripheral third are more likely to heal than those in the inner thirds.

Vertical peripheral longitudinal tears are the best scenario in terms of success when facing an AMR.

‘Inside-out’ techniques were considered as the gold standard for large repairs on mid-body and posterior parts of the meniscus. However, recent studies do not demonstrate differences regarding failure rate, functional outcomes and complications, when compared with the ‘all-inside’ techniques.

Some biological therapies try to enhance meniscal repair success but their efficacy needs further research. These are: mechanical stimulation, supplemental bone marrow stimulation, platelet rich plasma, stem cell therapy, and scaffolds and membranes.

Meniscal root tear/avulsion dramatically compromises meniscal stability, accelerating cartilage degeneration. Several options for reattachment have been proposed, but no differences between them have been established. However, repair of these lesions is actually the reference of the treatment.

Meniscal ramp lesions consist of disruption of the peripheral attachment of the meniscus. In contrast, with meniscal root tears, the treatment of reference has not yet been well established.

Cite this article: EFORT Open Rev 2018;3:584-594. DOI: 10.1302/2058-5241.3.170059

Hydrogels of agarose, and methacrylated gelatin and hyaluronic acid are more supportive for in vitro meniscus regeneration than three dimensional printed polycaprolactone scaffolds

In this study, porcine fibrochondrocyte-seeded agarose, methacrylated gelatin (GelMA), methacrylated hyaluronic acid (MeHA) and GelMA-MeHA blend hydrogels, and 3D printed PCL scaffolds were tested under dynamic compression for potential meniscal regeneration in vitro. Cell-carrying hydrogels produced higher levels of extracellular matrix (ECM) components after a 35-day incubation than the 3D printed PCL. Cells on GelMA exhibited strong cell adhesion (evidenced with intense paxillin staining) and dendritic cell morphology, and produced an order of magnitude higher level of collagen (p < 0.05) than other materials. On the other hand, cells in agarose exhibited low cell adhesion and round cell morphology, and produced higher levels of glycosaminoglycans (GAGs) (p < 0.05) than other materials. A low level of ECM production and a high level of cell proliferation were observed on the 3D printed PCL. Dynamic compression at 10% strain enhanced GAG production in agarose (p < 0.05), and collagen production in GelMA. These results show that hydrogels have a higher potential for meniscal regeneration than the 3D printed PCL, and depending on the material used, fibrochondrocytes could be directed to proliferate or produce cartilaginous or fibrocartilaginous ECM. Agarose and MeHA could be used for the regeneration of the inner region of meniscus, while GelMA for the outer region.

"Horizontal butterfly" technique in repair of radial meniscus tears: A biomechanical study

Introduction

Radial meniscus tears are seen in young patients, especially with anterior cruciate ligament ruptures. Repair of complete radial meniscus tear is necessary for the meniscus functions. The most important factor for success of the meniscus repair is primary stability, but it is still unknown which technique is ideal repair technique.

Aim

We developed a new suture technique named Horizontal Butterfly (HB). In this novel technique the contact between meniscal tissue and suture is more than Horizontal Loop (HL) that routinely used today. So, we think that this technique will provide better fixation than HL. We aimed to compare 2 repair techniques (HB vs. HL) using human lateral menisci biomechanically with cyclic loading and load to failure tests.

Material-method

We used 22 intact lateral meniscus obtained from patients that operated (total knee replacement) for varus gonarthrosis in our clinic. All menisci were cut radially. In the first group (n:11) menisci were repaired with standard horizontal loop technique, and in the second group (n:11) horizontal butterfly technique were used for repair. All specimens were tested with load to failure test after cyclic loading test (500 cycle X 5–30 N).

Results

Both groups have similar failure load (71,4 ± 17,52 N vs. 77,9 ± 28,49 N; p:0,559) and stiffness (24,46 ± 19,19 N vs. 24,48 ± 15,87 N; p:0,818). HB group has less peak displacement (6,26 ± 1,24 mm vs. 8,4 ± 1,92 mm; p:0,010).

Conclusion

This novel repair technique decreases the amount of displacement according to standard technique while as strong as standard technique routinely used. In this way; we believe that it will increase the rate of healing in clinical use.

Comparative Outcomes of All-Inside Versus Inside-Out Repair of Bucket-Handle Meniscal Tears: A Propensity-Matched Analysis

Background:

There are limited data comparing the outcomes of all-inside versus inside-out meniscal repair techniques.

Purpose:

To assess failure rates and clinical outcomes after the surgical repair of bucket-handle meniscal tears utilizing either an all-inside or inside-out technique.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Patients with bucket-handle meniscal tears undergoing all-inside or inside-out repair at a single institution between 2003 and 2013 were analyzed. A total of 28 mensici repaired utilizing second-generation all-inside suturing devices and 42 menisci repaired using an inside-out technique were eligible for inclusion. Rigorous propensity matching was performed on the basis of age, sex, tear laterality, rim width, and concomitant anterior cruciate ligament reconstruction (ACLR), resulting in a total of 40 patients equally distributed between the 2 repair techniques for comparison. Retear-free survival as well as preoperative and postoperative International Knee Documentation Committee (IKDC) and Tegner scores and physical examination findings were subsequently analyzed.

Results:

Twenty patients who underwent all-inside repair (14 male; mean age, 23.7 ± 6.7 years) were successfully propensity matched to 20 patients who underwent inside-out meniscal repair (15 male; mean age, 22.5 ± 7.6 years), with a mean retear-free follow-up of 4.4 years (range, 2.5-7.4 years). Four (20%) all-inside repairs and 4 (20%) inside-out repairs failed over the course of follow-up (P > .999), with a mean time to failure of 2.7 years (range, 1.3-4.4 years) and 5.0 years (range, 0.8-7.5 years), respectively (P = .25). Increasing patient age trended toward a decreased clinical retear rate, independent of the repair technique (hazard ratio, 0.86; P = .056). There were no significant differences in the Tegner scores, IKDC scores, or range of motion between the groups as a whole or when subcategorizing by age, sex, body mass index, tear complexity, rim width, isolated versus concomitant ACLR, or medial- versus lateral-sided repair. There were no complications in the all-inside group, while there was a 10% rate of minor complications in the inside-out group (P = .49).

Conclusion:

Overall, satisfactory clinical outcomes are achievable at short-term to midterm follow-up with both inside-out and all-inside repair techniques of bucket-handle meniscal tears in rigorously matched patients with similar meniscal tear patterns.

Concomitant meniscal injury in anterior cruciate ligament reconstruction does not lead to poorer short-term post-operative outcomes

PURPOSE

The main objective was to compare post-operative outcomes in patients undergoing anterior cruciate ligament (ACL) reconstruction both with and without concomitant meniscus injury at a mean follow-up of 3.5 years. The secondary objective was to study the effect of different meniscal injury sites and treatment modalities on post-operative outcomes (PROS).

METHODS

This is a retrospective analysis of a prospectively maintained database of patients undergoing ACL reconstruction at our tertiary institution between 2009 and 2012. Age, sex, graft type, graft fixation modality, location of meniscal tear and treatment (meniscal repair or meniscectomy) were recorded in the database. PROS used included the Tegner activity scale and the Lysholm score.

RESULTS

There were no significant differences between patients with or without meniscal injury in terms of age, BMI or preoperative PROS. There was no significant difference in the post-operative outcome scores between patients with or without meniscal injury at a mean follow-up of 3.5 years. Regardless of the location of meniscal injury, the post-operative scores improved as compared to preoperative scores.

CONCLUSION

Concomitant meniscal injury in cases of ACL reconstruction is not associated with poorer short-term post-operative PROS (mean follow-up time: 3.5 years). These findings may influence management decisions and help in preoperative counselling.

LEVEL OF EVIDENCE

IV.

Novel flat and wide meniscal repair material improves the ultimate load of knot breakage in a porcine trans-capsular meniscal repair model

Background

In the meniscal repair procedures, a high ultimate load capacity and low cyclic creep at the repair site are favorable and lead to good biological incorporation of the tear site after surgery. Previous biomechanical tensile tests of the meniscal sutures have identified the suture knot as the weakest point. We hypothesized that the strength of a suture knot depends on the suture shape, and therefore, we compared three differently shaped suture materials composed of the same material and quantity per length. The purpose of this study was to determine whether a novel flat and wide repair material (FWRM), which consists of braided multi-threads that are cross-sectionally flat and wide, improves the ultimate load of knot breakage in a biomechanical experiment using a porcine trans-capsular meniscal repair model.

Methods

Eighteen fresh-frozen porcine knees (n = 6 in each group) were used. A longitudinal tear in the middle segment of the medial meniscus was created and repaired with a trans-capsular inside-out method using the following suture materials: No. 2–0 braided polyester conventional suture, hollow suture, and FWRM. After the separation of the inner segment of the meniscus with leaving, the suture stability of the repaired menisci was biomechanically analyzed with a video camera system for widening after a cyclic load between 5 and 20 N was applied 300 times. Ultimate failure load and stiffness at 5 mm/ min were also analyzed.

Results

We found no significant difference in suture widening after cyclic load tests [conventional suture, mean 0.51 mm (S.D. 0.39 mm); hollow suture, mean 0.23 mm (S.D. 0.11 mm); and FWRM, mean 0.54 mm (S.D. 0.08 mm)]. The failure mode in all specimens was knot breakage. Compared with those of the other groups, the ultimate failure load of FWRM was statistically significantly higher in the load-to-failure tests (conventional suture, mean 58.8 N [S.D. 8.25 N]; hollow suture, mean 79.4 N [S.D. 10.2 N]; and FWRM, mean 97.4 N [S.D. 3.65 N]; p < 0.05).

Conclusion

FWRM improves the ultimate load of knot breakage without altering stability. This material may contribute to safe and stable meniscus repair.

Circumferential Suture Repair of Isolated Horizontal Meniscal Tears Augmented With Fibrin Clot

Traditionally, horizontal cleavage meniscus tears have been associated with osteoarthritis, indicative of the degenerative process. Recent treatment measures have focused on maintaining as much meniscal tissue as possible, despite the routine extension of these tears into the central white-white zones. In the absence of tunnel drilling for cruciate ligament reconstructions, the use of an exogenous fibrin clot is a useful adjunct to increase the local growth factors at the tear repair to aid in healing. This surgical technique is to describe the use of an all-arthroscopic tied circumferential suture repair of horizontal meniscal tears augmented with exogenous fibrin clot to treat all locations of horizontal meniscal tears.

Meniscal regeneration after resection of the anterior half of the medial meniscus in mice

Various animal studies have indicated that reduced meniscal function significantly exacerbates articular-cartilage degeneration. Despite the importance of meniscal function for joint homeostasis and prevention of osteoarthritis, the healing process after meniscal injury and the regenerative process after meniscus removal have not been studied in detail. In this study, we examined the process of meniscal regeneration and cartilage degeneration after meniscectomy in mice. The left anterior halves of the medial menisci in male C57Bl/6J mice were resected, and histological assessment of the process of meniscal regeneration was conducted on day 3 and 2, 4, and 6 weeks after the surgical procedure. Extensive macrophagic infiltration into the synovial membrane around the meniscectomized area was observed on day 3. Synovial hyperplasia was detected 2 weeks after the operation. At this stage, synovial tissue was filled with many fibroblastic cells, which underwent chondrocytic differentiation and produced cartilage matrices by 4 weeks after the operation. At 6 weeks, regenerated tissues resembled those of an intact meniscus. The articular cartilage at the interface of the resected meniscus significantly degenerated between 2 and 4 weeks after the surgical procedure, but subtle progression in cartilage degeneration was observed between 4 and 6 weeks. This finding is suggestive of a balance between meniscal regeneration and cartilage homeostasis. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1958-1965, 2017.