An MRI-based suspension bridge sign can predict an arthroscopically favorable meniscal healing following the medial meniscus posterior root repair

High-resolution magnetic resonance imaging can predict osteoarthritic progression after medial meniscus posterior root injury: randomized in vivo experimental study in a rabbit model

IMPORTANCE

The field of meniscal root preservation has undergone significant advancement over the past decades; however, the challenge remains to fully understand whether meniscal root repair can ultimately arrest or delay osteoarthritic changes.

OBJECTIVE

To assess longitudinal changes in articular cartilage, subchondral bone, and progression to meniscal extrusion (ME) using high-resolution magnetic resonance imaging (MRI).

METHODS

Medial meniscus posterior root tear was surgically induced in 39 New Zealand white rabbits. Animals were randomly assigned into three experimental groups: partial meniscectomy after root tear (PM, n ​= ​13); root tear left in situ (CT, n ​= ​13); and transtibial root repair (RR, n ​= ​13). Contralateral limbs were used as healthy controls. High resolution 4.7 Tesla MRI of the knee joint was performed at baseline, after 2-, and 4-months of post-surgery. Cartilage thickness was calculated in medial and lateral compartments. In addition, the evaluation of ME, subchondral bone edema and healing potential after root repair were assessed too.

RESULTS

Progressive cartilage thinning, ME, and subchondral bone edema were evident in all 3 study groups after 4-months of follow-up. The mean cartilage thickness in the PM group was 0.53 ​mm (±0.050), 0.57 ​mm (±0.05) in the CT group, and 0.60 ​mm (±0.08) in the RR group. The PM group exhibited significantly higher cartilage loss when compared to the CT and RR groups (p ​< ​0.001). Moreover, progressive ME and subchondral bone edema were associated with a more severe cartilage loss at the final follow-up.

CONCLUSION

Meniscal root repair did not halt but rather reduced the progression of osteoarthritis (OA). Degenerative changes worsened at a rapid rate in the PM group compared to the RR and CT groups. Early cartilage swelling, persistent subchondral edema, and progressive ME predicted a more severe progression to knee OA in the CT and RR groups.

LEVEL OF EVIDENCE

II.

Superior outcomes of pullout repairs for medial meniscus posterior root tears in partial tear compared to complete radial tear

PURPOSE

To reveal the outcomes of partial medial meniscus posterior root tears following transtibial pullout repair compared with the outcomes of complete radial meniscus posterior root tears.

MATERIALS AND METHODS

We retrospectively evaluated 15 consecutive patients (male/female, 5/10; average age, 64.4 years) who underwent transtibial pullout repair for partial medial meniscus posterior root tears and compared their results with those of 86 consecutive patients who underwent the same surgery for complete medial meniscus posterior root tears. All patients underwent second-look arthroscopy on average 1 year postoperatively, and a semi-quantitative meniscal healing score (anteroposterior width, stability, and synovial coverage, total 10 points) was evaluated. Medial meniscus extrusion was evaluated preoperatively and at second-look arthroscopy.

RESULTS

Postoperative clinical scores were not significantly different in the short term. However, second-look arthroscopy revealed a significant difference in repaired meniscal stability (partial tear; 3.3 points, complete tear; 2.3 points, p < 0.001) and total meniscal healing scores (partial tear; 8.3 points, complete tear; 7.1 points, p < 0.001). Medial meniscus extrusion progression was significantly different (partial tear; 0.4 mm, complete tear; 1.0 mm, p < 0.001).

CONCLUSION

Partial medial meniscus posterior root tears showed better meniscal healing and less medial meniscus extrusion progression following pullout repair than complete medial meniscus posterior root tears.

Clinical outcomes of medial meniscus posterior root repair: A midterm follow-up study

BACKGROUND

Transtibial pullout repair of medial meniscus posterior root tears (MMPRTs) cannot prevent the progression of knee osteoarthritis. Conversions of knee arthroplasties are occasionally required following MMPRT repair. However, other knee-related surgical treatments following MMPRT repair are unclear. This study was aimed at investigating the midterm clinical outcomes and knee-related surgical events following MMPRT repair.

METHODS

Patients with MMPRT underwent pullout repair using FasT-Fix modified Mason-Allen (F-MMA) suturing with an all-inside meniscal repair device. Thirty-two patients with follow-up duration >2 years were enrolled. We assessed the clinical outcomes and postoperative surgical treatment of both knees.

RESULTS

F-MMA pullout repair improved all clinical evaluation scores in patients with MMPRT at a mean follow-up of 36.1 months. Postoperative arthroscopic debridement was required for one patient. An additional MMPRT repair was performed in one patient on second-look arthroscopy. None of the patients required ipsilateral knee arthroplasty. In the contralateral knees, one pullout repair of a newly developed MMPRT and two knee arthroplasties were performed.

CONCLUSIONS

This study demonstrated that F-MMA pullout repair yielded satisfactory clinical outcomes. However, subsequent knee-related surgeries were observed in 6.3% of the pullout-repaired knees and 9.4% of the contralateral knees. Our results suggest that surgeons should be aware of the worsening and/or occurrence of contralateral knee joint disease, even when the postoperative clinical outcomes are satisfactory following MMPRT repair.

LEVEL OF EVIDENCE

IV.

Arthroscopic Meniscal Healing following Medial Meniscus Posterior Root Repair: A Comparison between Two Suture Materials

Recently, transtibial pullout repair of the medial meniscus (MM) posterior root tear (PRT) has become widely accepted and provides satisfactory clinical outcomes. Widening after cyclic loading or ultimate failure load using different suture materials and configurations has been studied. However, no study has compared the clinical outcomes using different suture materials. This study aimed to evaluate the clinical outcomes after performing MMPRT pullout repair using different suture materials. We hypothesized that better clinical outcomes would be achieved using ultra-high molecular weight polyethylene (UHMWPE) tape compared with a normal polyester suture. Thirty-seven patients who underwent MM posterior root repair between November 2019 and May 2020 were retrospectively investigated. Pullout repair was performed using a hollow no. 0 polyester suture (n = 14) and UHMWPE tape (n = 23). Clinical outcomes were assessed preoperatively and at 1 year postoperatively, using the Lysholm knee score, Knee Injury and Osteoarthritis Outcome Score, and visual analogue scale (VAS) pain score. The meniscal healing status was assessed using an arthroscopic scoring system (range: 0-10). All clinical scores were improved significantly in both groups. However, significantly higher meniscal healing scores and decreased VAS pain scores were observed in the UHMWPE group (7.3 ± 0.9 and 7.7 ± 11.3, respectively) than in the polyester group (5.6 ± 2.1 and 18.4 ± 18.6, respectively; p < 0.01). Suture cut-out and loss of the root continuity were observed in some cases (three cases [21.4%] in the polyester suture group and one case [4.3%] in the UHMWPE tape group). Both suture materials led to satisfactory clinical outcomes at 1 year postoperatively, whereas the UHMWPE tape was useful for obtaining good meniscal healing and decreasing the VAS pain score.

Examining the Efficacy of Medial Meniscus Posterior Root Repair: A Meta-analysis and Systematic Review of Biomechanical and Clinical Outcomes

BACKGROUND

Medial meniscus posterior root (MMPR) injuries accelerate the progression of osteoarthritis. While partial meniscectomy was once considered the gold standard for treatment, meniscus root repair has become increasingly utilized with reported improvements in clinical and biomechanical outcomes.

PURPOSE

To perform a systematic review of biomechanical outcomes and a meta-analysis of clinical and radiographic outcomes after MMPR repair.

STUDY DESIGN

Meta-analysis and systematic review; Level of evidence, 4.

METHODS

The PubMed, Embase, and Cochrane databases were queried in August 2021 for studies reporting biomechanical, clinical, and radiographic outcomes after MMPR repair. Biomechanical studies were assessed for main results and conclusions. Data including study characteristics, cohort demographics, and outcomes were extracted. Included clinical studies were analyzed with a random-effects meta-analysis of proportions for binary outcomes or continuous outcomes for mean differences between preoperative and postoperative time points. Subgroup analysis for studies reporting repair outcomes with concomitant high tibial osteotomy (HTO) was performed where appropriate.

RESULTS

A total of 13 biomechanical studies were identified and reported an overall improvement in mean and peak contact pressures after MMPR repair. There were 24 clinical studies, consisting of 876 patients (877 knees), identified, with 3 studies (106 knees) reporting outcomes with concomitant HTO. The mean patient age was 57.1 years (range, 23-74 years), with a mean follow-up of 27.7 months (range, 2-64 months). Overall, clinical outcomes (Lysholm, Hospital for Special Surgery, International Knee Documentation Committee, visual analog scale for pain, Tegner, and Knee injury and Osteoarthritis Outcome Score scores) were noted to improve postoperatively compared with preoperatively, with improved Lysholm scores in patients undergoing concomitant HTO versus MMPR repair alone. Meniscal extrusion was not significantly improved after MMPR repair compared with preoperative measurements. The progression in Kellgren-Lawrence grades from grade 0 to grades 1 to 3 occurred in 5.9% (21/354) of patients after repair, with no patients progressing from grades 1 to 3 to grade 4.

CONCLUSION

MMPR repair generally improved biomechanical outcomes and led to improved patient-reported outcomes with greater improvements noted in patients undergoing concomitant HTO. Repair did not significantly improve meniscal extrusion, while only 5.9% of patients were noted to progress to low-grade osteoarthritis. The high level of heterogeneity in the included biomechanical and clinical investigations emphasizes the need for more well-designed studies that evaluate outcomes after MMPR repair.

Midterm Outcomes of Posterior Medial Meniscus Root Tear Repair: A Systematic Review

BACKGROUND

Whereas there has been growing interest in surgical repair of posterior medial meniscus root tears (PMMRTs), our understanding of the medium- and long-term results of this procedure is still evolving.

PURPOSE

To report midterm clinical outcomes from PMMRT repairs.

STUDY DESIGN

Systematic review.

METHODS

A literature review for this systematic analysis was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We identified studies that reported the results of arthroscopic repair of PMMRTs. Functional and imaging outcomes were reviewed and summarized.

RESULTS

In total, 28 studies with a total of 994 patients (83% female) with an overall mean age of 57.1 were included in this review. Clinical outcomes (Lysholm, International Knee Documentation Committee, Hospital for Special Surgery, and Tegner scores) were improved at final follow-up in all studies. Of patients, 49% had radiographic progression of at least 1 grade in the Kellgren-Lawrence scale at a mean follow-up of 4.0 years in 11 studies. Cartilage degeneration had progressed at least 1 grade on magnetic resonance imaging scans in 23% of patients at a mean follow-up of 31.6 months in 4 studies.

CONCLUSION

PMMRT repairs provide a functional benefit with consistent improvements in clinical outcome scores. There is some evidence that PMMRT repair slows the progression of osteoarthritis but does not prevent it at midterm follow-up.

Medial meniscus posterior root repairs: A comparison among three surgical techniques in short-term clinical outcomes and arthroscopic meniscal healing scores

BACKGROUND

Medial meniscus (MM) posterior root repairs lead to favorable clinical outcomes in patients with MM posterior root tears (MMPRTs). However, there are few comparative studies in evaluating the superiority among several pullout repair techniques such as modified Mason-Allen suture, simple stitch, and concomitant posteromedial pullout repair. We hypothesized that an additional pullout suture at the MM posteromedial part would have clinical advantages in transtibial pullout repairs of the MMPRTs. The aim of this study was to compare the clinical usefulness among several types of pullout repair techniques in patients with MMPRTs.

METHODS

Eighty-three patients who underwent arthroscopic pullout repairs of the MMPRTs were investigated. Patients were divided into three groups using different pullout repair techniques: a modified Mason-Allen suture using FasT-Fix all-inside meniscal repair device (F-MMA, n = 28), two simple stitches (TSS, n = 30), and TSS concomitant with posteromedial pullout repair using all-inside meniscal repair device (TSS-PM, n = 25). Postoperative clinical outcomes and semi-quantitative arthroscopic meniscal healing scores (0-10 points) were evaluated at second-look arthroscopies.

RESULTS

No significant differences among the three groups were observed in patient demographics and preoperative clinical scores, except for preoperative Lysholm scores. At second-look arthroscopies, there were no significant differences among the three techniques in postoperative clinical outcomes and meniscal healing scores.

CONCLUSIONS

This study demonstrated that the TSS-PM pullout repair technique did not show better scores in postoperative clinical outcomes and meniscal healings compared with the F-MMA and TSS techniques. Our results suggest that the concomitant posteromedial pullout suture may have no clinical advantage in the conventional pullout repairs for the patients with MMPRTs.

Lateral meniscal posterior root tears experience acceptable healing status after transtibial repair technique

PURPOSE

To evaluate patient MRI results, demography and clinical outcome following transtibial repair of lateral and medial meniscal posterior root tears.

METHODS

Patients treated with transtibial repairs of posterior meniscal root tears from 2015 through 2018 performed pre- and postoperative MRI scans. Outcome measures were continuity/discontinuity of the meniscal root and change in meniscal extrusion on MRI. Other outcomes were KOOS, Lysholm score, Tegner activity scale and the Global Rate of Change (GRoC) score for function and pain at follow-up.

STUDY DESIGN

Retrospective case-series.

RESULTS

Of 41 patients, 36 attended follow-up at mean 26 (12-38) months postoperatively. At follow-up, 11 out of 18 lateral meniscus posterior root tear (LMPRT) versus 5 out of 18 medial meniscus posterior root tear (MMPRT) repairs were classified as healed. Meniscal extrusion decreased in LMPRTs from of 2.3 ± 1.5 mm to 1.4 ± 1.09 mm (p = 0.080) and increased in MMPRTs from 3.1 ± 1.6 mm to 4.8 ± 1.9 mm (p = 0.005) at FU (between-group difference, p < 0.001). LMPRT repairs were associated with ACL injury and additional meniscal injury and were younger and with lower BMI. No between-group differences were found for KOOS, Lysholm or GRoC Function scores. Tegner scale was higher and GRoC Pain score lower in the LMPRT group compared to the MMPRTs.

CONCLUSION

Following transtibial repair for meniscal posterior root repairs, the LMPRTs had a higher frequency of healing, whereas most MMPRTs continued to extrude, despite surgical intervention. The study confirmed that LMPRTs and MMPRTs differ in demography and associated injuries.

Postoperative clinical outcomes of unicompartmental knee arthroplasty in patients with isolated medial compartmental osteoarthritis following medial meniscus posterior root tear

Background

Cartilage degradation progresses rapidly following medial meniscus posterior root tear (MMPRT). Unicompartmental knee arthroplasty (UKA) has been performed for medial compartmental osteoarthritis following MMPRT. We evaluated the clinical and radiographic outcomes of UKA for medial compartmental osteoarthritis after an untreated MMPRT.

Methods

Twenty-one patients who underwent UKA for isolated medial compartment osteoarthritis following MMPRT were retrospectively investigated. Clinical outcomes were assessed using the Knee Injury and Osteoarthritis Outcome Score and knee range of motion. The posterior tibial slope and tibial component inclination were evaluated using plain radiographs.

Results

The mean follow-up periods were 25.5 ± 13.8 months. Clinical outcomes improved significantly postoperatively. The mean postoperative knee extension angle was −1.1° ± 2.1°, and the knee flexion angle was 134.3° ± 4.9°. The posterior tibial slope angle decreased from 9.0° ± 2.0° preoperatively to 5.4° ± 1.8° postoperatively, and postoperative tibial component inclination at the final follow-up was 2.9° ± 1.1° varus. No aseptic loosening or deep infections were observed.

Conclusion

UKA significantly improved clinical outcomes and could be a viable surgical option for treating isolated medial compartmental osteoarthritis accompanied by untreated MMPRT.

Association Between Transtibial Meniscus Root Repair and Rate of Meniscal Healing and Extrusion on Postoperative Magnetic Resonance Imaging: A Prospective Multicenter Study

Background:

Prospective studies evaluating second-look imaging of meniscus root repair using a transtibial pull-out technique are limited; therefore, optimal surgical indications and the technique for meniscus root repair remain uncertain.

Hypothesis:

It was hypothesized that there would be a high rate of healing, improvement in meniscal extrusion, and prevention of articular cartilage degeneration and subchondral bone abnormalities after meniscus root repair.

Study Design:

Case series; Level of evidence, 4.

Methods:

Consecutive patients undergoing transtibial root repair were prospectively enrolled at 2 orthopaedic centers between March 2017 and January 2019. Pre- and postoperative magnetic resonance imaging (MRI) scans were reviewed by a musculoskeletal radiologist in a blinded fashion for meniscal healing, quantification of extrusion, articular cartilage grade, subchondral bone changes, and coronary/meniscotibial ligament abnormalities. Given persistent extrusion observed on postoperative MRI scans, an additional 10 patients gave consent and were enrolled for immediate (before weightbearing) postoperative MRI scans.

Results:

A total of 45 patients (16 male, 29 female; mean ± standard deviation age, 42.3 ± 12.9 years; body mass index, 31.6) were prospectively enrolled in the study; there were 47 meniscus root repairs: 29 medial and 18 lateral (2 with both). Postoperative MRI was obtained at an average of 6.3 months (range, 5.1-8 months); 98% of meniscal repairs had evidence of healing. Mean extrusion increased significantly, from 1.9 ± 1.5 mm preoperatively to 2.6 ± 1.4 mm postoperatively (P = .03). There was no significant progression of chondromalacia grade, subchondral edema, insufficiency fracture, subchondral cysts, or subchondral collapse. In the additional 10-patient cohort, the mean preoperative extrusion (1.6 ± 1.2 mm) was not significantly different from that immediately postoperatively (2.0 ± 1.0 mm; P = .23).

Conclusion:

Prospective MRI analysis of transtibial meniscus root repair confirmed a high rate of meniscal healing and no observable progression of cartilage degeneration or subchondral bone abnormalities at the short-term follow-up. However, meniscal extrusion worsened in the first 6 months after surgery.

Registration:

NCT03037242 (ClinicalTrials.gov identifier).

Transtibial pullout repair techniques using two simple stitches for medial meniscus posterior root tear can prevent the progression of medial meniscus extrusion and obtain successful outcomes

PURPOSE

Transtibial pullout repairs using two simple stitches (TSS) and a combination of TSS with posteromedial pullout repair (TSS + PMP) using an all-inside meniscal repair device have been reported previously for the treatment of medial meniscus (MM) posterior root tears. This study aimed to investigate the postoperative clinical outcomes of these techniques including MM extrusion (MME).

METHODS

Fifty-two patients who underwent transtibial pullout repair were investigated and divided into TSS (n = 27) and TSS + PMP (n = 25) groups. The clinical outcomes were assessed using the Lysholm knee score and Knee Injury and Osteoarthritis Outcome Score 1 year postoperatively and compared between two groups. MME was measured using magnetic resonance imaging at 1 year postoperatively and compared between two groups.

RESULTS

A significant improvement in each clinical score was observed in both groups, and no significant difference was seen in clinical outcomes. Moreover, no significant difference in postoperative MME was observed in both groups (TSS and TSS + PMP: 3.5 mm and 3.8 mm, respectively). Though no significant progression of MME was observed in TSS group, a significant progression of it was observed in TSS + PMP group postoperatively.

CONCLUSIONS

This study demonstrated that both techniques improved clinical outcomes in the short-term postoperative period. However, MME was progressed significantly in TSS + PMP group 1 year postoperatively, which indicated that PMP might not be a useful additional procedure for reducing the postoperative MME.

Arthroscopic Medial Meniscal Posterior Root Repair With Transtibial Luggage-Tag and Horizontal Mattress Sutures

Medial meniscal posterior root repair techniques have shown positive yet varied results in the literature. The decision to perform repair has improved clinical outcomes in many situations, although the healing rate is approximately 64% and the repair strength is roughly one-third of the native root strength, with meniscal extrusion being common. We present a technique based on biomechanical evidence to obtain a strong anatomic posterior root repair to restore nearly normal knee mechanics, combining an increased size of footprint under the lateral aspect of the medial meniscal horn for healing and a luggage-tag suture with a posteriorly placed horizontal mattress suture. The horizontal mattress suture is passed to capture the circumferential fibers of the meniscus and the luggage-tag suture is passed to capture the radial fibers of the meniscal body, through a single transtibial tunnel. The aim of this repair is to restore the normal meniscal function.

Preoperative morphologic changes of the medial meniscus correlate with suture translations during knee flexion in pullout repair of medial meniscus posterior root tear

BACKGROUND

Medial meniscus (MM) translates and extrudes posteriorly during knee flexion in MM posterior root tear (MMPRT) knees, and transtibial pullout repair of MMPRT has been performed to regulate the MM extrusion. This study aimed to calculate each suture translation during knee flexion in transtibial pullout repair of MMPRT, and to investigate the morphologic features of the MM that lead to longer suture translations during knee flexion.

METHODS

Thirty patients with MMPRT who met the operative indication of pullout repair were enrolled and investigated prospectively. Pullout repair was performed by using two simple stitches (outer and inner sutures) and an all-inside suture in the posteromedial part of the MM. Each suture's translation from 0° to 90° of knee flexion was measured intraoperatively. The MM morphologic features, including MM medial extrusion (MMME) and MM posterior height (MMPH), were measured using preoperative magnetic resonance imaging, and the correlation between these values and each suture translation was evaluated.

RESULTS

The average outer, inner, and all-inside suture translations were 4.8 mm, 3.9 mm, and 1.3 mm, respectively. Significant correlations were observed between the outer suture translation and MMME, and MMPH (p < 0.001 and <0.01, respectively). The thresholds for preoperative MMME and MMPH for longer outer suture translations (≥6 mm) were 2.1 mm and 5.4 mm, respectively.

CONCLUSIONS

Preoperative longer MMME and higher MMPH were associated with longer meniscus translations during knee flexion during MMPRT repair.

Two simple stitches for medial meniscus posterior root repair prevents the progression of meniscal extrusion and reduces intrameniscal signal intensity better than modified Mason-Allen sutures

PURPOSE

Medial meniscus posterior root tears (MMPRTs) can cause severe medial extrusion of the medial meniscus (MMME) and the progression of knee degenerative changes, inducing a high signal intensity of the meniscus on magnetic resonance imaging (MRI). Although MMME and intrameniscal signal intensity (IMSI) reportedly decreased within 3 months after MMPRT repair, no previous studies have reported these changes after a 1-year follow-up. This study aimed to investigate the 1-year postoperative changes in MMME and IMSI on MRI after using different suture techniques.

METHODS

Overall, 33 patients with MMPRT were evaluated, 22 underwent FasT-Fix-dependent modified Mason-Allen suture (F-MMA) repair, and 11 underwent two simple stitches (TSS) repair. MRI examinations were performed preoperatively and 1 year postoperatively. MMME and IMSI were determined using MRI.

RESULTS

A significant decrease in postoperative MMME was observed in the TSS group (4.1 ± 1.0) relative to that in the F-MMA group (5.1 ± 1.4, P = 0.03). A significant decrease in postoperative IMSI (0.75 ± 0.14) was observed relative to preoperative IMSI in the TSS group (P < 0.01), whereas postoperative IMSI (0.94 ± 0.25) was similar to preoperative IMSI in the F-MMA group (P = 0.06). Furthermore, a significant decrease in postoperative IMSI was observed in the TSS group relative to that in the F-MMA group (P < 0.01).

CONCLUSIONS

The most important finding of this study is that TSS repair yielded a greater decrease in MMME and IMSI than F-MMA repair in patients with MMPRT. These results suggest that TSS repair is more useful for restoring loading stress to the posterior horn of the medial meniscus.