Rehabilitation Following Meniscal Root Repair: A Clinical Commentary

Meniscus root tears: what is the hype?

ABSTRACT

Meniscus root tears are increasingly being studied due to their importance in meniscus function. Meniscus root tears can increase the joint contact pressure significantly, similar to a total meniscectomy. This may cause rapid progression of joint degeneration and produce inferior clinical outcome. Historically, they were treated with partial meniscectomy, which did not change the natural history. New repair techniques such as transtibial pull-out repair and suture anchor repair have improved the clinical outcome. This review article summarises the anatomy of the meniscus, the pathology of meniscus root tears and different repair techniques with their clinical outcomes.

Comparison of Functional Outcomes after Anterior Cruciate Ligament Reconstruction with Meniscal Repair for Unstable versus Stable Meniscal Tears

This study aimed to compare functional outcomes including knee muscle strength in the quadriceps and hamstrings, and proprioception, assessed through dynamic postural stability (overall stability index [OSI]) and self-reported outcomes in the operated and non-operated knees between anterior cruciate ligament reconstruction (ACLR) with meniscal repair for unstable (root and radial tears) and stable (longitudinal, horizontal, and bucket handle tears) meniscal tears. A total of 76 patients were randomly selected (41 with ACLR with meniscal repair for unstable meniscal tears and 35 with ACLR with meniscal repair for stable meniscal tears) at three different time points (preoperative, 6 months, and 12 months). Repeated measures analysis of variance was used to investigate the differences in outcomes for between-subject and within-subject factors. In the operated knees, there were no significant differences for functional outcomes between the two groups (all p > 0.05). In the non-operated knees, a significant difference was observed for the OSI between the two groups, which was significantly higher in ACLR with meniscal repair for unstable meniscal tears than for stable meniscal tears at 6 months (p < 0.001). Multiple linear regression analysis showed that age (p = 0.027), preoperative OSI in the operated knees (p = 0.005), and postoperative OSI in the operated knees at 6 months (p = 0.002) were significant and independent predictors for OSI in the non-operated knees at 6 months postoperatively. Therefore, while no differences were observed in functional outcomes between the two groups in the operated knees, dynamic postural stability was poorer at 6 months postoperatively in the non-operated knees of patients with ACLR with meniscal repair for unstable meniscal tears. Furthermore, a significant correlation was observed between preoperative/postoperative dynamic postural stability in the operated knees and postoperative dynamic postural stability in the non-operated knees. Hence, we recommend incorporating balance exercises for both knees in post-surgical rehabilitation, particularly for patients with unstable meniscal tears.

Meniscus root tears: state of the art

BACKGROUND

Meniscus root tears represent significant pathology that, historically, has been underdiagnosed and undertreated. However, the recognition of their clinical and functional significance has recently surged, mainly due to their frequent association with anterior cruciate ligament injuries.

AIM

This comprehensive review discusses various aspects of meniscal root tears, including their epidemiology, biomechanics, etiology, clinical and radiological findings, classification, management and surgical techniques.

Increased Posterior Tibial Slope Increases Force on the Posterior Medial Meniscus Root

BACKGROUND

Posterior medial meniscus root (PMMR) tears have been associated with increased posterior tibial slope, but this has not been fully evaluated biomechanically. In addition, the effects of knee flexion and rotation on the PMMR are not well understood biomechanically because of technological testing limitations. A novel multiaxial force sensor has made it possible to elucidate answers to these questions.

PURPOSE

(1) To determine if increased posterior tibial slope results in increased posterior shear force and compression on the PMMR, (2) to evaluate how knee flexion angle affects PMMR forces, and (3) to assess how internal and external rotation affects force at the PMMR.

STUDY DESIGN

Controlled laboratory study.

METHODS

Ten fresh-frozen cadaveric knees were tested in all combinations of 3 posterior tibial slopes and 4 flexion angles. A multiaxial force sensor was connected to the PMMR and installed below the posterior tibial plateau maintaining anatomic position. The specimen underwent a 500-N compression load followed by a 5-N·m internal torque and a 5-N·m external torque. The magnitude and direction of the forces acting on the PMMR were measured.

RESULTS

Under joint compression, an increased tibial slope significantly reduced the tension on the PMMR between 5° and 10° (from 13.5 N to 6.4 N), after which it transitioned to a significant increase in PMMR compression, reaching 7.6 N at 15°. Under internal torque, increased tibial slope resulted in 4.7 N of posterior shear at 5° significantly changed to 2.0 N of anterior shear at 10° and then 8.2 N of anterior shear at 15°. Under external torque, increased tibial slope significantly decreased PMMR compression (5°: 8.9 N; 10°: 4.3 N; 15°: 1.1 N). Under joint compression, increased flexion angle significantly increased medial shear forces of the PMMR (0°, 3.8 N; 30°, 6.2 N; 60°, 7.3 N; 90°, 8.4 N). Under internal torque, 90° of flexion significantly increased PMMR tension from 2.3 N to 7.5 N. Under external torque, 30° of flexion significantly increased PMMR compression from 4.7 N to 12.2 N.

CONCLUSION

An increased posterior tibial slope affects compression and anterior shear forces at the PMMR. An increased flexion angle affects compression, tension, and medial shear forces at the PMMR.

CLINICAL RELEVANCE

The increase in compression and posterior shear force when the knee is loaded in compression may place the PMMR under increased stress and risk potential failure after repair. This study provides clinicians with information to create safer protocols and improve repair techniques to minimize the forces experienced at the PMMR.

Rehabilitation after Repair of Medial Meniscus Posterior Root Tears: A Systematic Review of the Literature

Background

There is no consensus established on postoperative rehabilitation after medial meniscus posterior root tear (MMPRT) repair, including when and how physicians can apply range of motion (ROM) exercise, weight-bearing (WB), brace use, and return to sports (RTS). The purpose of this study was to systematically review the literature on postoperative rehabilitation characteristics of MMPRT repair regarding ROM, WB, brace use, and RTS.

Methods

A literature search was performed using the Medline/PubMed, Cochrane Central Register of Controlled Trials, and Embase databases. The inclusion criteria were English language, human clinical studies, and studies describing rehabilitation protocols after MMPRT repair such as ROM, WB, brace use, and RTS. Abstracts, case reports, cohort studies, controlled laboratory studies, human cadaveric or animal studies, systematic reviews, and meta-analyses were excluded.

Results

Thirteen studies were included. Of the 12 ROM studies, ROM was started immediately within 1 or 2 days after operation in 6 studies and after 2 to 3 weeks of knee immobilization in the rest. Of the 13 WB studies, partial weight-bearing was initiated 1 to 4 weeks after operation in 8 studies and 6 weeks in the rest. Of the 9 brace studies, patients were immobilized by a splint for 2 weeks in 3 studies, and in the rest, a brace with full extension was applied for 3 to 6 weeks after several days of splint application. Of the 7 RTS studies, RTS was allowed at 6 months in 6 studies and 5 to 7 months in 1 study.

Conclusions

This systematic review revealed conservative rehabilitation protocols were more widely adapted as ROM and WB were restricted at certain degrees during postoperative periods in most protocols analyzed. However, it is impossible to identify a consensus on rehabilitation protocols as the protocols analyzed in this review were distinct each other and heterogeneous. In the future, a well-designed comparative study among different rehabilitation protocols is essential to establish a consensus.

Return-to-sport criteria after isolated meniscus suture: Scoping review of the literature

BACKGROUND

Follow-up care including rehabilitation therapy after isolated meniscal repair remains to be standardized. Thus, no standard criteria are available for the return-to-running (RTR) or return-to-sport (RTS). The objective of this study was to identify criteria for RTR and RTS after isolated meniscal repair, based on a review of the literature.

HYPOTHESIS

Return-to-sport criteria after isolated meniscal repair have been published.

METHODS

We performed a scoping review of the literature using the methodology developed by Arksey and O'Malley. The terms "menisc*" and "repair" and "return-to-sport" or "return to play" or "return to run" or "rehabilitation" were used to search the PubMed database on 1st March 2021. All relevant studies were included. All RTR and RTS criteria were identified, analyzed, and classified.

RESULTS

We included 20 studies. Mean RTR and RTS times were 12.9 and 20 weeks, respectively. Clinical, strength, and performance criteria were identified. The clinical criteria included full range-of-motion recovery with no pain, quadriceps wasting, or joint effusion. Strength criteria were a quadriceps and hamstring deficit, no greater than 30% and 15% for RTR and RTS, respectively, compared to the normal side. Performance criteria were successful completion of proprioception, balance, and neuromuscular tests. RTS rates ranged from 80.4% to 100%.

CONCLUSION

Patients must meet clinical, strength, and performance criteria before resuming running and sports. The level of evidence is low, due to the heterogeneity and generally arbitrary choice of criteria. Further large-scale studies are therefore needed to validate and standardize RTR and RTS criteria.

LEVEL OF EVIDENCE

IV.

The Impact of Meniscal Tear Type and Surgical Treatment on Quadriceps Strength: A Study of Adolescent Patients Post Anterior Cruciate Ligament Reconstruction

BACKGROUND

Treatment of meniscal injuries at the time of anterior cruciate ligament reconstruction (ACLR) can result in restrictions on weightbearing and range of motion in the early rehabilitative phases. What is unknown is the effect of (1) meniscal tear type and location at the time of anterior cruciate ligament injury and (2) meniscal treatment at the time of ACLR on quadriceps strength in adolescents during the late rehabilitative phase.

HYPOTHESIS

Meniscal tears involving the root and requiring repair would adversely affect quadriceps strength at 6 to 9 months postoperatively.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who underwent ACLR at 1 of 2 research sites between 2013 and 2021 were identified. Adolescent participants were included if they were between the ages of 12 and 20 years at the time of assessment and had undergone primary unilateral ACLR in the previous 6 to 9 months. Participants were subgrouped by meniscal tear type (no tear, nonroot tear, root tear) and meniscal treatment at the time of ACLR (no treatment, meniscectomy, meniscal repair), which were confirmed via chart review. Isokinetic strength testing occurred at 60 deg/s, and quadriceps strength and quadriceps strength limb symmetry index were compared between the meniscal tear type and meniscal procedure subgroups using analysis of covariance while controlling for the effects of age, sex, and ACLR graft source.

RESULTS

An overall 236 patients were included in this analysis (109 male, 127 female; mean ± SD age, 16.0 ± 1.9 years). There were no significant differences in ACLR limb quadriceps strength based on meniscal tear type (P = .61) or meniscal procedure at the time of ACLR (P = .61), after controlling for age, biological sex, and ACLR graft source. Similarly, quadriceps strength limb symmetry index did not differ by meniscal tear type (P = .38) or meniscal procedure at the time of ACLR (P = .40).

CONCLUSION

Meniscal tear type and treatment at the time of ACLR did not affect quadriceps strength or quadriceps strength symmetry in adolescents 6 to 9 months after ACLR.

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

Background

Meniscal extrusion is a phenomenon in which a degenerative posterior horn tear, radial tear, or root tear results in displacement of the body of the meniscus medial to the tibial rim. The paramount function of the meniscus is to provide load distribution across the knee joint. Meniscal extrusion will prevent the meniscus from properly fulfilling this function and eventually leads to progression of osteoarthritis1. Thus, root repair accompanied by arthroscopic meniscal extrusion repair (by a centralization technique) has been suggested for restoration of meniscal function2-5. There are various techniques to correct meniscal extrusion, including a dual-tunnel suture pull-out technique2 (to address extrusion and root tear2), a knotless suture anchor4,6 technique, and an all-inside suture anchor repair7. The indications for extrusion repair are not consistently reported in the literature, and the procedure is not always easy to perform. Currently, there is no consensus regarding the ideal technique. In the present article, we describe the steps for successful combined medial meniscal root repair with extrusion repair and centralization.

Description

Place the patient in the supine position with the knee supported in 90° of flexion and the feet at the edge of the operating table with foot-positioner support. First, meniscal root repair is performed with use of the suture pull-out technique, utilizing a cinch suture configuration to hold the root in place, and the suture tapes are fixed over the anterior cortex of the tibia with a suture button. Next, the meniscal body is arthroscopically assessed for residual extrusion from the medial tibial rim. Extrusion repair is indicated in cases with >3 mm of extrusion7-9, as measured on magnetic resonance imaging. In our technique, any extrusion beyond the medial tibial rim is reduced and secured with use of a double-loaded 2.3-mm all-suture type of anchor.

Alternatives

Alternatives include surgical procedures in which the root repair is performed with use of suture-anchor fixation10,11 and the extrusion repair is performed with use of the transtibial suture pull-out method.

Rationale

Root repair performed with the most common fixation techniques does not always reduce meniscal extrusion or restore meniscal function12,13. Consequently, several augmentation techniques have been reported to address meniscal extrusion3,14, including those that use arthroscopy to centralize the midbody of the meniscus over the rim of the tibial plateau. The rationale for this combined procedure is to restore the hoop-stress distribution and maintain meniscal function by repairing the extrusion of the meniscus. Addressing all intra-articular pathologies in a single stage is a challenging situation, and the sequence of the repair is important to achieve optimal postoperative results.

Expected Outcomes

Several surgical techniques have been described for the operative treatment of extrusion repair with use of centralization sutures2,3,5,6, and each has its own distinctive pearls and pitfalls for each. To combine root repair and extrusion repair presents a challenge for surgeons. From our clinical experience, a methodical approach to understanding the pathoanatomy and sequential execution of repair techniques would yield desired results. Extrusion correction through the use of a peripheral suture anchor over the medial rim of the tibia and knot tying are relatively easier to perform than some other published extrusion-repair techniques. Although no consensus has been achieved yet regarding the best technique, recent literature has suggested that the use of centralization sutures is effective to restore the native biomechanical properties of the medial meniscus5.Mochizuki et al. assessed the clinical and radiological outcomes of combined medial meniscal root repair and centralization in 26 patients with a minimum follow-up of 2 years. Both Lysholm scores and Knee injury and Osteoarthritis Outcome Scores improved significantly after surgery, with a significant reduction in extrusion distance from preoperatively to 2 years postoperatively20. Koga et al21 assessed the 2-year outcomes of lateral arthroscopic meniscal centralization, finding significantly reduced meniscal extrusion at both 3 months and 1 year postoperatively. Biomechanical studies have demonstrated that centralization can improve meniscal mechanics and potentially reduce the risk of osteoarthritis. The centralization suture technique for extrusion repair has the theoretical advantage of restoring meniscal function following meniscal root repair; however, there are also concerns regarding over-constraint of the meniscus. We believe that the medial meniscus, being less mobile than the lateral meniscus, can withstand the constraint created by the use of centralization. Meniscal centralization is a technically demanding surgical procedure, but with a systematic approach and meticulous technique, we have observed good short-term outcome in our patients.

Important Tips

A tight medial compartment is one of the most common problems encountered during a medial meniscal root repair. "Pie-crusting" of the superficial medial collateral ligament at the tibial insertion aids in improving the space, thereby reducing chondral damage during the root repair.It is challenging to achieve the correct inclination of insertion when inserting the suture anchor through a mid-medial portal. This limitation can be mitigated by utilizing a 16G or 18G needle before making the portal, as the needle direction, trajectory, and extent of accessibility within the joint will aid in proper portal placement and anchor insertion.Suture management is another technical challenge. Suture tape is first cinched to the root of the meniscus and then shuttled into the transtibial tunnel in order to discern the reducibility of the meniscus and the extent of possible extrusion correction. Then, extrusion repair is performed. This sequence allows the surgeon to avoid mixing of root-repair sutures and extrusion-repair sutures. Following insertion of the all-suture anchor, each suture limb is brought out through the anteromedial portal, passed through the nitinol loop from the lasso, and shuttled back through the mid-medial portal. Knot tying is performed through the mid-medial portal.

Acronyms and Abbreviations

ACL = anterior cruciate ligamentPCL = posterior cruciate ligamentICRS grading = International Cartilage Research Society system for classification of cartilage lesionsKL grade = Kellgren-Lawrence system for classification of osteoarthritisMRI = magnetic resonance imagingMC = medial femoral condyleMPTA = medial proximal tibial angleLC = lateral femoral condyleHTO = high tibial osteotomyMCL = medial collateral ligamentAM = anteromedialKOOS = Knee injury and Osteoarthritis Outcome ScoreMME = medial meniscus extrusion.

Medial Meniscus Posterior Root Tear: How Far Have We Come and What Remains?

Medial meniscus posterior root tears (MMRTs), defined as tears or avulsions that occur within 1 cm of the tibial attachment of the medial meniscus posterior root, lead to biomechanically detrimental knee conditions by creating a functionally meniscal-deficient status. Given their biomechanical significance, MMRTs have recently been gaining increasing interest. Accordingly, numerous studies have been conducted on the anatomy, biomechanics, clinical features, diagnosis, and treatment of MMRTs, and extensive knowledge has been accumulated. Although a consensus has not yet been reached on several issues, such as surgical indications, surgical techniques, and rehabilitation protocols, this article aimed to comprehensively review the current knowledge on MMRTs and to introduce the author's treatment strategies.

Are Outcomes of Acute Meniscus Root Tear Repair Better Than Debridement or Nonoperative Management? A Systematic Review

BACKGROUND

Meniscus root tears (MRTs) are defined as radial tears within 1 cm of the meniscus root insertion or an avulsion of the meniscus root itself. They lead to altered joint loading because of the failure to convert axial (compressive) loads into hoop stresses. Untreated MRTs can result in altered joint biomechanics and accelerated articular cartilage degeneration and the development of osteoarthritis (OA), yet optimal management remains unclear.

PURPOSE

To review treatment outcomes after acute MRTs by surgical repair, debridement, meniscectomy, or nonoperative treatment.

DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of the evidence from human clinical studies was conducted with electronic searches of the PUBMED, Medline, EMBASE, and the Cochrane Library databases. One reviewer extracted the data and 2 reviewers assessed the risk of bias and performed synthesis of the evidence.

RESULTS

Eleven studies of low to moderate methodological quality were identified. All treatment options improved functional scores after >12 months. Arthroscopic repair may be associated with better functional outcomes when compared with partial meniscectomy and nonoperative management at 12-month follow-up. Radiographic progression of OA occurred in all treatment groups; there was some evidence that this was delayed after repair when compared with other treatments. Baseline severity of meniscal extrusion, varus malalignment, and pretreatment degeneration were predictors of poor functional outcomes. Age was not found to be an independent predictor of functional outcome.

CONCLUSION

The current level 3 and 4 evidence suggests that arthroscopic repair may result in slower progression of radiological deterioration compared with meniscectomy and nonoperative management. The current literature does not support the exclusion of patients from MRT repair on the basis of age. Patients undergoing acute MRT treatments (repair, debridement, or nonoperative) can be expected to experience improvement in functional outcomes after >12 months. The strength of conclusions are limited because of the paucity of high-quality studies on this subject. Further studies, preferably randomized sham controlled trials with function-oriented rehabilitation programs, are needed to compare treatment strategies and stratification of care based on the risk of meniscal extrusion.

REGISTRATION

CRD42018085092 (PROSPERO).

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.

The functional impact of home-based self-rehabilitation following arthroscopic meniscus root repair

BACKGROUND

Corona virus infectious pandemic makes outdoors rehabilitation a potential hazard. Patient education to perform simple home-based exercises seems to be an interesting and sometimes a mandatory option. This study provides a comparison between the conventional and home-based virtual rehabilitation after surgical repair of medial meniscus root tears.

METHODS

In this prospective study, all patients who underwent medial meniscus posterior root repair with a modified trans-tibial pull-out technique from March 2019 to March 2021 were evaluated. Those who underwent surgery after December 2019 were trained to perform self-rehabilitation. The rest had undergone outdoors specialized rehabilitation according to a unified protocol and these were used as a historical control group. All patients were followed up for a minimum of 2 year after surgery. Final Lysholm scores were utilized to compare functional outcomes after considering the effect of age, body mass index and time from surgery by multivariate linear regression analysis.

RESULTS

Forty-three consecutive patients with medial meniscal root tears were studied. Thirty-nine (90.7%) were women and 4 (9.3%) were men. The mean age of participants was 53.2 ± 8.1 years. The total Lysholm knee score, and all its items were significantly improved in both groups at a two-year follow-up (p < 0.05), except the "Using cane or crutches" item (p = 0.065). Nevertheless, the final Lysholm knee score improvement was higher in patients who performed outdoors specialized rehabilitation and in patients with shorter time-to-surgery.

CONCLUSION

Regardless of age and gender, home-based rehabilitation after meniscal root repair with the modified trans-tibial pull-out technique improved the patients' function at a two-year follow-up. Nonetheless, this effect was still significantly lower than that of the outdoors specialized rehabilitation. Future work is required to clarify basic protocols for home-based tele-rehabilitation programs and determine clinical, radiological and functional results.

LEVEL OF EVIDENCE

Level IV, therapeutic, historically controlled study.

Meniscus Root Tears: A Clinical Review

ABSTRACT

Meniscus root tears are important to recognize early given their potentially devastating consequences on joint health. This injury results in the lost ability of the meniscus to transfer axial loads into hoop stress; therefore, it is functionally equivalent to a complete meniscectomy. This causes rapid progression of osteoarthritis and increased need to total knee arthroplasty in a previously healthy joint. Despite these consequences, root tears have only been discussed in the orthopedic literature in the last 10 to 15 years and have not been routinely integrated into nonoperative sports medicine education. It is important for all nonoperative sports medicine providers to properly diagnose and triage this injury early in its course to maximize joint preservation efforts. The goal of this manuscript is to review the anatomy, presentation, natural history, imaging, and treatment options for meniscal root tears.

Outcomes of Combined Lateral Meniscus Posterior Root Repair and Anterior Cruciate Ligament Reconstruction

Background:

Lateral meniscus posterior root tears (LMPRTs) almost always occur in association with anterior cruciate ligament (ACL) tears. Their repair is advocated to restore the stabilizing and load-sharing functions of the meniscus.

Purpose:

To study the functional outcomes of combined arthroscopic repair of LMPRTs and ACL reconstruction (ACLR).

Study Design:

Case series; Level of evidence, 4.

Methods:

The authors evaluated patients who underwent simultaneous arthroscopic ACLR and LMPRT repair. All patients had chronic injuries, with a mean time since ACL rupture of 7.9 months. Patient characteristics, Lachman and pivot-shift test results, type of LMPRT, associated injuries, and surgery details were documented. Pre- and postoperative functional status was assessed using the International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score (KOOS), and Lysholm score. An independent single-tunnel transtibial repair using 2 SutureTapes was performed for Forkel type 1 and 3 tear root avulsions, while side-to-side suture repair was performed for type 2 radial/oblique tears. The Wilcoxon signed rank test and minimal clinically important difference (MCID) of the IKDC score were used for statistical analysis.

Results:

Included were 25 patients with a mean age of 29.6 ± 6.5 years. Of these, 22 patients (88%; 95% CI, 73.1%-100%) had a high-grade (grade 2 or 3) preoperative pivot shift. Diagnosis of the LMPRT on magnetic resonance imaging (MRI) scans was possible only in 5 patients (20%). At final evaluation, performed at 37.4 ± 7.1 months postoperatively, all functional scores had improved significantly from preoperatively: IKDC score, from 47.6 ± 9.5 to 81.8 ± 11.5; KOOS, from 45.5 ± 10.9 to 86.5 ± 10.3, and Lysholm score, from 49.0 ± 11.5 to 88.8 ± 7.6 (P < .001 for all). Twenty-four patients (96%) achieved the MCID for the IKDC score. All knees had a negative pivot shift at final analysis, and no patient underwent revision ACLR or LMPRT repair.

Conclusion:

LMPRT repair combined with ACLR led to good short-term clinical outcomes in this study. An LMPRT may frequently go undetected on preoperative MRI scans, but a high-grade pivot shift is present in a large majority of these patients.

Platelet-rich plasma (PRP) augmentation does not result in more favourable outcomes in arthroscopic meniscal repair: a meta-analysis

Background

The efficacy and safety of platelet-rich plasma (PRP) augmentation for arthroscopic meniscal repair is controversial. This meta-analysis compared arthroscopic meniscal repair performed in isolation or augmented with PRP.

Methods

The present study was conducted according to PRISMA 2020 guidelines. Pubmed, Web of Science, Google Scholar and Embase were accessed in August 2021. All the clinical trials which compared arthroscopic meniscal repair performed in isolation or augmented with PRP were included.

Results

Eight hundred thirty-seven patients were included: 38% (318 of 837 patients) were women; the mean age of the patients was 35.6 (range, 20.8–64.3) years; the mean follow-up was 26.2 (range, 6–54) months. Similarity was found in analogue scale (VAS) (P = 0.5) and Lysholm (P = 0.9), and International Knee Documentation Committee (IKDC) scores (P = 0.9). Similarity was found in the rate of failure (P = 0.4) and rate of revision (P = 0.07).

Conclusion

The current published scientific evidence does not support PRP augmentation for arthroscopic meniscal repair.

The modifying factors that help improve anterior cruciate ligament reconstruction rehabilitation: A narrative review

BACKGROUND

The goal of a rehabilitation programme after anterior cruciate ligament (ACL) reconstruction is to manage a patient's goals and expectations (i.e., returning to physical activities and sports) while minimizing the risk of new injury, particularly a new ACL injury. Although general rehabilitation programmes have been proposed, some factors can lead to adapting each programme to each patient.

OBJECTIVE

To describe how different variables, including surgical techniques, sports participation, psycho-social and contextual factors can modify the rehabilitation programme.

METHODS

We performed a narrative review with input from experts in the field (level of evidence 5).

CONCLUSIONS

Modifying factors of the ACL rehabilitation programme are related to the initial lesion or surgery, to sports, or to psychological or social aspects. Regarding the type of graft, the rehabilitation is mainly different in the early postoperative phase; the other phases are not graft-based but rather goal-based rehabilitation. Depending on the meniscal or cartilage repair, the rehabilitation protocol will initially take priority over the anterior cruciate ligament reconstruction protocol. The ACL reconstruction rehabilitation programme should meet the requirements of the anticipated sports, to optimize the athlete's ability to return to the expected level and minimize the risk of reinjury. Psycho-social and contextual factors must also be considered in rehabilitation care to individualize and optimize each patient's programme.

[Posterior meniscus root tears]

Meniscus root tears are radial tears in the region of the posterior insertion zones. Medial root injuries usually occur in individuals > 50 years of age without adequate trauma and are associated with obesity and varus deformities. The root lesion leads to a loss of ring tension, which results in extrusion of the meniscus and a strong increase in joint pressure that is biomechanically equivalent to a complete meniscectomy. When indicating arthroscopic transosseous refixation of the medial root lesion, factors such as accompanying cartilage damage, osteoarthritis, obesity and varus deformity must be taken into account. Injuries to the root of the lateral meniscus are mostly observed in younger patients in combination with a rupture of the anterior cruciate ligament. Arthroscopic transosseous refixation in combination with cruciate ligament surgery is therefore also recommended for type I and type II lesions. In summary, both the medial and the lateral root lesions of the menisci are injuries with high biomechanical relevance.

H-Plasty Repair Technique Improved Tibiofemoral Contact Mechanics After Repair for Adjacent Radial Tears of Posterior Lateral Meniscus Root: A Biomechanical Study

PURPOSE

To compare the time-zero tibiofemoral contact mechanics among the 4 different suturing repairs: transtibial pullout suture repair, suture anchor repair, side-to-side repair, and H-plasty repair.

METHODS

Twenty-four human cadaveric knees were included. Each lateral meniscus condition (intact, radial tear, and repair) was tested under a 1000-N axial compressive load at 0°, 30°, 60°, and 90° of flexion. Four different repair techniques, transtibial pullout, suture anchor, side-to-side, and H-plasty repair technique, were tested. Tibiofemoral mean and peak contact pressure and contact area in the lateral and medial compartments were measured by Tekscan sensors.

RESULTS

Radial tears adjacent to the posterior lateral meniscus root produced significantly decreased contact area and increased mean and peak contact pressures in the lateral compartment across all angles (P < .05). All repair groups could improve the contact mechanics relative to the torn condition (P < .05), but only H-plasty repair showed no significant difference in the mean and peak contact pressure and contact area compared with that of the intact state at all flexion angles (P > .05).

CONCLUSIONS

The results showed that the tibiofemoral contact mechanics after adjacent radial tears of the posterior lateral meniscal root were improved to the intact level by H-plasty repair at time-zero. The additional vertical mattress sutures act as "stabilizers" to provide a more stable environment in distributing vertical tibiofemoral pressure. The other 3 repair techniques also significantly improved lateral tibiofemoral contact mechanics relative to the corresponding tear conditions.

CLINICAL RELEVANCE

The results of this study suggest that H-plasty repair can restore the biomechanical properties to the intact state. Since it was a time-zero cadaveric study, the results should be carefully used in clinical practices.

Meniscal repair: The current state and recent advances in augmentation

Meniscal injuries represent one of the most common orthopedic injuries. The most frequent treatment is partial resection of the meniscus, or meniscectomy, which can affect joint mechanics and health. For this reason, the field has shifted gradually towards suture repair, with the intent of preservation of the tissue. "Save the Meniscus" is now a prolific theme in the field; however, meniscal repair can be challenging and ineffective in many scenarios. The objectives of this review are to present the current state of surgical management of meniscal injuries and to explore current approaches being developed to enhance meniscal repair. Through a systematic literature review, we identified meniscal tear classifications and prevalence, approaches being used to improve meniscal repair, and biological- and material-based systems being developed to promote meniscal healing. We found that biologic augmentation typically aims to improve cellular incorporation to the wound site, vascularization in the inner zones, matrix deposition, and inflammatory relief. Furthermore, materials can be used, both with and without contained biologics, to further support matrix deposition and tear integration, and novel tissue adhesives may provide the mechanical integrity that the meniscus requires. Altogether, evaluation of these approaches in relevant in vitro and in vivo models provides new insights into the mechanisms needed to salvage meniscal tissue, and along with regulatory considerations, may justify translation to the clinic. With the need to restore long-term function to injured menisci, biologists, engineers, and clinicians are developing novel approaches to enhance the future of robust and consistent meniscal reparative techniques.

Continuous Meniscal Suture in Radial Meniscal Tear: The Hourglass Technique

The key to preventing early knee osteoarthritis is meniscal preservation. The main functions of the meniscus are impact absorption, mechanical load transmission, lubrication, joint stability, and proprioception. Radial lesions that extend to the joint capsule are called complete radial tears. This type of injury compromises 2 of the main meniscal functions, which are impact absorption and load distribution, which is equivalent, from a biomechanical perspective, to a total meniscectomy. In the recent past, the treatment of choice for this type of injury was partial meniscectomy. However, several studies have observed progressive joint degeneration after this type of treatment. Recently, different types of meniscal sutures involving radial lesions of the meniscus have been developed. It is believed that such repairs may bring a decrease in future osteoarthritis in this patient profile. The purpose of this article is to describe the steps of continuous meniscal suture for the treatment of radial tears of the medial and lateral menisci.

Posterior Root Repair of Medial Meniscus Combined With Valgus Opening Wedge Tibial Osteotomy

The medial meniscal root tear, a particular meniscal injury at the level of its posterior bone insertion, leads to a loss of impact absorption and load distribution capacity, similar to total meniscectomy. Therefore, its repair is fundamental for knee joint longevity. This type of injury often occurs in middle-aged patients with lower limbs varus malalignment, which results in mechanical overloading of the medial compartment and induces premature cartilage wear out. The success of meniscal root repair, with meniscal bone reinsertion, depends on the correction and realignment of varus deformities greater than 5° for physiological levels. In this situation, corrective tibial osteotomy combined with meniscal repair is indicated. Our goal is to describe the step-by-step technique of the valgus opening wedge tibial osteotomy combined with the arthroscopic reinsertion of the posterior meniscal root in tibia during the treatment of a patient with varus deformity and medial meniscus root tear.

Muscle strength but not balance improves after arthroscopic biodegradable polyurethane meniscus scaffold application

PURPOSE

This study aimed to assess the impact of biodegradable polyurethane meniscus scaffold implantation (BPMSI) on muscle strength and balance in comparison with the healthy contralateral knee in patients with irreparable medial meniscus defect.

METHODS

This observational and prospective case-cohort study was conducted with patients who had irreparable meniscal defects and underwent arthroscopic meniscus scaffold implantation. Surgeries were carried out on the medial meniscus of 16 right and 4 left knees. Visual analog scale (VAS) was used to assess the degree of pain relief. Knee Injury and Osteoarthritis Outcome Score (KOOS) and Lysholm (LYS) score were used to evaluate the functional improvement at weeks 12, 24 and 36. Concentric and eccentric quadriceps and hamstring peak torque (PT) as well as the peak torque-to-body weight (PTB) ratio, anterior-posterior, mediolateral and overall stability indexes were assessed at the same time points.

RESULTS

Twenty male patients with a mean age and body mass index of 32.2 ± 8.8 years and 26.2 ± 4.2 kg/m², respectively, were included in the study. The amount of pain decreased from 7.6 ± 1.5% to 2.9 ± 1.5% at postoperative week 36. Range of motion, Lysholm score and KOOS increased from 87.0^ο ± 9.5^ο to 115.0^ο ± 15.1^ο, 30.8 ± 4.3 to 81.5 ± 5.3 and 37.4 ± 5.3 to 74.1 ± 7.2, respectively. Concentric quadriceps and hamstring peak torque values and peak torque/body weight ratios were improved in the knees that received a meniscus scaffold implant. Anterior/posterior, medial/lateral, and overall stability indexes with or without biofeedback exhibited a slight improvement, which was not statistically significant.

CONCLUSION

BPMSI led to decreased pain and improved function at postoperative week 36. Although muscle strength almost returned to normal, balance parameters did not recover within 36 weeks after the procedure.

Peripheral Stabilization Suture to Address Meniscal Extrusion in a Revision Meniscal Root Repair: Surgical Technique and Rehabilitation Protocol

Meniscal root tears are an increasingly recognized condition. These tears can cause the meniscus to become extruded outside the joint, which can diminish the biomechanical functionality of the meniscus. Anatomic repair of the meniscal root has previously been described, but this surgical procedure may not adequately address severe extrusion of the meniscal tissue. Additionally, when a primary anatomic repair fails, meniscal extrusion can increase, which can possibly accelerate joint degeneration if untreated. Therefore, the purpose of this Technical Note is to describe our surgical technique for revision medial meniscal root repair with a peripheral stabilization suture to address medial meniscal root tears with severe meniscal extrusion.

Medial Meniscus Root Repair in Patients With Open Physes

Meniscal root tears have become increasingly recognized in the past decade. Lateral meniscus root tears typically occur in active, younger patients who sustain acute anterior cruciate ligament tears. Conversely, medial meniscus root tears typically occur in isolation and affect middle-aged patients. However, recent reports have described the incidence of meniscal root tears occurring in pediatric populations who are skeletally immature. The purpose of this technical note is to describe the authors' surgical technique for medial meniscal root repair for patients with open physes.

Type II Medial Meniscus Root Repair With Peripheral Release for Addressing Meniscal Extrusion

Medial meniscal root tears are often disabling injuries that can occur in isolation during low-velocity, deep knee flexion maneuvers in middle-aged patients. The most common meniscal root tear pattern is a radial tear near the root attachment (type II). Root tears are often associated with meniscal extrusion, identified on magnetic resonance imaging. Relocation of the meniscal root to its anatomic center is a reported current difficulty faced by surgeons during surgical repair. However, this can be achieved via sufficient peripheral release of the posteromedial capsular attachment of the medial meniscus. The purpose of this Technical Note is to describe the authors' current surgical technique for medial meniscus root repair with a peripheral release for addressing meniscal extrusion. Classifications: level I (knee); level II (meniscus).

Editorial Commentary: Meniscal Root Repairs: Let the Biology Help You!

Meniscal root tears are increasingly being recognized as important entities by the orthopaedic community. This is probably due to the catastrophic consequences of not identifying or addressing a root tear in a timely fashion, leading to the need for a total meniscectomy. The majority of the studies on root tears have been focused on natural history, diagnosis, biomechanical consequences, and fixation techniques. Conversely, rehabilitation concepts have been extrapolated from those applied after other meniscal tears/repairs, even though root tears probably constitute a completely different pathology from biological and biomechanical standpoints. Time zero studies are important to determine the effect of certain loads on the repaired structure without taking into consideration the healing process. This allows for examination of the effects that an accelerated protocol would have in the immediate postoperative phase after a root repair. As with any repaired structure, allowing time for the repaired tissue to heal is vital because failing to do so might lead to unrecoverable failure of the root fixation.

[Meniscal root lesions: clinical relevance and treatment]

Meniscal roots play an important role in load distribution of the tibiofemoral knee joint. Thus, meniscal root tears are severe injuries of the knee, which significantly expose cartilage to increased stress. Two entities are distinguished: (i) acute root tears that mainly affect the posterolateral root and often occur with ruptures of the anterior cruciate ligament; and (ii) chronic, degenerative root tears that mainly affect the posteromedial root. For diagnosis of both entities, the patient's medical history, a knee examination and especially MRI play key roles. The treatment of choice is in general transtibial fixation of the torn root, which leads to an increased clinical improvement and a decrease of the progression of arthritis.

Understanding posterior meniscal roots lesions: from basic science to treatment

The variability of symptoms and the fact that they are not easily recognized in imaging studies make the diagnosis and treatment of posterior meniscal roots lesions a challenging task to the orthopedist. In recent years, a more precise understanding of the anatomy and biomechanical impair of the knee joint in these cases has enabled great advances in therapeutic approaches. Well-documented studies have shown that the repair of these lesions presents superior functional and clinical improvement when compared with meniscectomy. However, the progression of degenerative joint changes in the long-term still exhibits conflicting results.

Posterior Meniscal Root Repairs: Outcomes of an Anatomic Transtibial Pull-Out Technique

BACKGROUND

Outcomes after transtibial pull-out repair for posterior meniscal root tears remain underreported, and factors that may affect outcomes are unknown. Purpose/Hypothesis: The purpose of this study was to compare patient-centered outcomes after transtibial pull-out repair for posterior root tears in patients <50 and ≥50 years of age. We hypothesized that improvement in function and activity level at minimum 2-year follow-up would be similar among patients <50 years of age compared with patients ≥50 years and among patients undergoing medial versus lateral root repairs.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Inclusion criteria were patients aged 18 years or older who underwent anatomic transtibial pull-out repair of the medial or lateral posterior meniscus root by a single surgeon. All patients were identified from a data registry consisting of prospectively collected data in a consecutive series. Cohorts were analyzed by age (<50 years [n = 35] vs ≥50 years [n = 15]) and laterality (lateral [n = 15] vs medial [n = 35]). Patients completed a subjective questionnaire preoperatively and at minimum of 2 years postoperatively (Lysholm, Tegner, Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], 12-Item Short Form Health Survey [SF-12], and patient satisfaction with outcome). Failure was defined as revision meniscal root repair or partial meniscectomy.

RESULTS

The analysis included 50 knees in 49 patients (16 females, 33 males; mean age, 38.3 years; mean body mass index, 26.6). Of the 50 knees, 45 were available for analysis. Three of 45 (6.7%) required revision surgery. All failures were in patients <50 years old, and all failures underwent medial root repair. No significant difference in failure was found based on age ( P=.541) or laterality ( P = .544). For age cohorts, Lysholm and WOMAC scores demonstrated significant postoperative improvement. For laterality cohorts, all functional scores significantly improved postoperatively. No significant difference was noted in postoperative Lysholm, WOMAC, SF-12, Tegner, or patient satisfaction scores for the age cohort or the laterality cohort.

CONCLUSION

Outcomes after posterior meniscal root repair significantly improved postoperatively and patient satisfaction was high, regardless of age or meniscal laterality. Patients <50 years had outcomes similar to those of patients ≥50 years, as did patients who underwent medial versus lateral root repair. Transtibial double-tunnel pull-out meniscal root repair provided improvement in function, pain, and activity level, which may aid in delayed progression of knee osteoarthritis.