Medial meniscus posterior root repair decreases posteromedial extrusion of the medial meniscus during knee flexion

Modified Mason-Allen vs Two Simple Stitch Fixation for Medial Meniscus Posterior Root Tears: A Systematic Review and Meta-analysis

BACKGROUND

Various suture configurations are available for medial meniscus posterior root tear (MMPRT) repair. The modified Mason-Allen (MMA) technique has been proposed as a refixation technique for MMPRT instead of the conventional 2 simple stitches (TSS). This is in view of its superior biomechanical characteristics.

PURPOSE

To perform a systematic review and meta-analysis to compare MMA and TSS configuration techniques for MMPRT repair and identify any differences between the 2 techniques in terms of clinical outcomes, medial meniscal extrusion (MME), and postoperative healing.

STUDY DESIGN

Meta-analysis; Level of evidence, 4.

METHODS

The Cochrane Controlled Register of Trials, PubMed, Medline, and Embase databases were used to perform a systematic review and meta-analysis using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria with the following search terms: ("meniscus" OR "meniscal injuries") AND ("Mason-Allen" OR "simple stitch" OR "suture techniques"). Data pertaining to all patient-reported outcome measures, postoperative complications, MME, postoperative healing, cartilage degeneration, and progression of knee osteoarthritis were extracted from each study. The pooled outcome data were analyzed using random- and fixed-effects models.

RESULTS

After abstract and full-text screening, 6 clinical studies were included. In total, there were 291 patients; 160 underwent MMA fixation, and 131 underwent the TSS technique. The majority of studies had similar surgical techniques regarding repair technique, suture material, tibial fixation, and number and position of tibial tunnels. There were no differences between the groups in terms of patient-reported outcome measures at 14.2 months. Both techniques were also similar in the degree of postoperative MME and meniscal healing.

CONCLUSION

Both suture configurations were equivalent in terms of clinical outcomes, the extent of meniscal extrusion, and postoperative healing. The TSS technique may offer advantages in terms of faster learning curve and shorter operative time. However, randomized controlled trials with large sample sizes, longer follow-up and assessment of chondral degeneration, and presence of knee osteoarthritis are required to assess whether a true difference exists, as the majority of included studies were limited by their retrospective design.

Initial tension at suture fixation affects the suture breakage following medial meniscus posterior root repair: A retrospective cohort study

OBJECTIVES

This study aimed to investigate whether the initial suture tension when pullout sutures are fixed affects postoperative clinical outcomes following medial meniscus posterior root repair.

METHODS

The data of 48 patients who underwent transtibial pullout repair using two simple stitches (outer and inner sutures) with an additional all-inside posteromedial pullout were retrospectively investigated. The patients were sequentially divided into two groups to compare the clinical efficacy of the initial pullout tension (N) when pullout sutures were fixed: the 30 N Group (April 2019 to September 2019, 24 patients) and the 15 N group (October 2019 to February 2020, 24 patients). The rate of suture breakage (suture cutout or rupture) at the second-look arthroscopy at 1 year postoperatively and clinical outcomes at 2 years postoperatively were compared between the two groups.

RESULTS

In both groups, each clinical score significantly improved at 2 years postoperatively. At the second-look arthroscopy, the rate of posteromedial suture breakage was significantly higher in the 30 N group (19 patients, 79 ​%) than in the 15 N group (10 patients, 42 ​%); the rate of outer suture breakage was also higher in the 30 N group (five patients, 21 ​%) than in the 15 N group (no patients). On comparing 2 years of preoperative clinical scores between the groups categorized according to posteromedial suture breakage, the pain score was significantly higher in the suture breakage group.

CONCLUSIONS

The initial tension of pullout repair of the medial meniscus posterior root tear is related to suture breakages. To prevent suture breakage, 15 N is a more initially suitable condition than 30 N.

LEVEL OF EVIDENCE

Level III.

Differences Between Traumatic and Degenerative Medial Meniscus Posterior Root Tears: A Systematic Review

BACKGROUND

Intact meniscus roots are a prerequisite for normal meniscal function, including even distribution of compressive forces across the knee joint. An injury to the root disrupts the hoop strength of the meniscus and may lead to its extrusion and the development of osteoarthritis. A medial meniscus posterior root tear (MMPRT) is often thought to have a primary degenerative pathogenesis. However, there is mention of some cases of MMPRTs where the patients have a solely traumatic injury to a previously healthy meniscus.

PURPOSE

To describe a subpopulation of patients with traumatic MMPRT.

STUDY DESIGN

Systematic review; Level of evidence, 5.

METHODS

The Web of Science database (www.webofscience.com) was queried using the Medical Subject Headings term "medial root tear." Articles were reviewed, and those evaluated for MMPRTs in a degenerative meniscus were excluded. A total of 25 articles describing cases of acute traumatic causes were included in this study. For these articles, the patient characteristics, injury mechanisms, and concomitant injuries evaluated were recorded and pooled.

RESULTS

The search revealed 660 articles, and 25 were selected for inclusion. A total of 113 patients with a traumatic MMPRT were identified and included in this review. The study population had a mean age of 27.1 years and a high share of men (64%). Also, this review displays how most patients with traumatic MMPRTs also suffer concomitant injuries (68%).

CONCLUSION

The findings in this review support our hypothesis that there is a unique subgroup with acute traumatic MMPRTs that have unique patient characteristics, injury mechanisms, and combined injuries, compared with previously published reviews on MMPRTs.

Figure-4 Patient Positioning Increases Medial Meniscus Extrusion on Ultrasound in Patients With Posterior Medial Meniscus Root Tears of the Knee

Purpose

To compare the degree of medial meniscal extrusion (MME) between knees with medial meniscus posterior root tear (MMPRT) and degenerative tears of the medial meniscus using ultrasonography (US) in different limb positions and to identify the findings characteristic of MMPRT.

Methods

The study group comprised 25 subjects with MMPRT (group RT), 25 subjects with degenerative medial meniscal tears (group D), and 25 knees with no abnormalities of the medial meniscus (MM) on magnetic resonance imaging (MRI) (group C) whose age was ≥40 years. MME was evaluated using US in the supine, figure-4, feet-dangling, and standing positions. The MME was evaluated by the actual measurement values and the relative values to the MME in the supine position. The differences in the MME among the 3 groups in each limb position were analyzed using one-way analysis of variance. P < .05 was considered significant.

Results

The actual MME values were largest in group RT in all 4 limb positions. When changing the limb position from the supine to the figure-4, the actual MME increased from 3.8 ± 0.8 mm to 5.5 ± 1.3 mm in group RT, whereas it decreased from 3.4 ± 1.1 mm to 1.8 ± 1.2 mm in group D, showing the most significant difference in MME of the figure-4 position between the 2 groups (P < .001). In group RT, 88% of knees had the maximum MME in the figure-4 position. In group D, 60% of knees had the maximum MME in the standing position and only 2 knees (8%) had the maximum MME in the figure-4 position.

Conclusions

The increase in MME from the supine to the figure-4 position was a characteristic finding of MMPRT but not degenerative tears.

Level of Evidence

Level III, case-control study.

Concomitant posterior anchoring further reduces posterior meniscal extrusion during pullout repair of medial meniscus posterior root tears: a retrospective study

PURPOSE

Transtibial pullout repair improves the clinical outcomes of medial meniscus (MM) posterior root tears (PRTs); however, reducing MM extrusion remains challenging. Thus, the purpose of this study was to examine the role of additional posterior anchoring (PA) during pullout repair in reducing the severity of MM extrusion compared to pullout repair alone.

METHODS

Patients who underwent pullout repair with two-cinch stitches (TCS) only or TCS combined with PA (TCS-PA)-deployment of an additional suture anchor in the posteromedial corner of MM-were included retrospectively. MM medial and posterior extrusion (MMME and MMPE), MM extrusion and remaining volume (MMEV and MMRV), and corresponding ratios were evaluated pre-operatively and three months post-operatively using a three-dimensional meniscal model at 10° and 90° of knee flexion and compared within and between groups.

RESULTS

A total of 15 and 16 patients treated with TCS and TCS-PA, respectively, were enrolled. At 90° knee flexion, both techniques significantly reduced MMPE (TCS: 4.2 ± 0.7 mm to 3.5 ± 0.6 mm, p < 0.05; TCS-PA: 3.7 ± 0.8 mm to 2.8 ± 0.7 mm, p < 0.05) at three months post-operatively. TCS-PA reduced MMPE more significantly than TCS alone (p < 0.05). Only TCS-PA significantly improved the MMEV and MMRV ratios (39.6 ± 8.9% to 28.1 ± 6.0%, p < 0.05 and 60.4 ± 8.9% to 71.9 ± 6.0%, p < 0.05, respectively). Significance was not found in all other comparisons.

CONCLUSIONS

Both techniques improved MMPE at knee flexion at the three month follow-up, with TCS-PA providing significantly superior results. Our findings support the evidence that the application of PA may be an effective surgical option for alleviating persistent MMPE.

Etiology of posterior meniscus root tears: medial vs. lateral

PURPOSE

The aim of this study was to generate more information on the etiology and pathogenesis of medial (MM) and lateral (LM) meniscus root tears. Our hypothesis was that root tears of the MM predominantly result from degenerative damage, whereas root injuries of the LM are mainly of traumatic origin.

METHODS

Consecutively, 53 patients with a root tear of the medial meniscus (MMRT) and 51 patients with a root tear of the lateral meniscus (LMRT) were included in this study. The diagnosis was confirmed radiologically by MRI as well as arthroscopically. In addition to patient-specific data such as age, BMI and trauma history, the leg axis was determined and accompanying injuries (ligamentous and chondrogenic) were documented.

RESULTS

The mean age of the MMRT group was 57.2 (± 11.2) years, and that of the LMRT group 33.9 (± 11.4) years. The BMI was significantly higher in the MMRT group compared to the LMRT (30.5 vs. 25.1). 82.4% of patients in the LMRT group demonstrated an accompanying anterior cruciate ligament (ACL) rupture, whereas only 5.7% of the MMRT were associated with an ACL injury. A trauma was described in only 13.2% of patients of the MMRT group in contrast to 88.2% of the LMRT group. An extrusion > 3 mm of the MM in the coronal plane of MRI images could be detected in 86.8% of patients, whereas in the LMRT group, it was 15.7%. The mechanical varus angle was 5.6° in the MMRT group and 2.4° in the LMRT group. The rate and degree of concomitant cartilage damage in the affected compartment was significantly higher in the group with medial root injuries than in the group with lateral root tears.

CONCLUSIONS

The root injuries of the MM and LM show significant differences in terms of patient age, etiology and accompanying injuries. Root injuries to the medial meniscus are mostly of non-traumatic origin and more likely to occur in the context of medial osteoarthritis and varus deformity of the knee. Lateral root tears tend to be predominantly traumatic and are frequently associated with ACL ruptures. However, in the MMRT group, a small subgroup with a traumatic etiology and in the LMRT group a small subgroup of patients with non-traumatic etiology could be identified.

LEVEL OF EVIDENCE

III.

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.

Medial meniscus posterior root repair influences sagittal length and coronal inclination of the anterior cruciate ligament: a retrospective study

PURPOSE

Medial meniscus (MM) posterior root tears (PRTs) lead to abnormal kinematic changes in the knee and may induce pathological external rotation of the tibia during knee flexion. This study aimed to investigate changes in the length and inclination of the anterior cruciate ligament (ACL) after MM posterior root repair using magnetic resonance imaging (MRI).

METHODS

This retrospective study included 44 patients who underwent MM posterior root repair between 2016 and 2019. Clinical outcomes were evaluated before and after surgery. MRI examinations were performed at 10°/90° of knee flexion preoperatively and 3 months postoperatively. The ACL length, proximal angle, and distal angle were determined using the sagittal view. MM extrusion and ACL inclination angle were determined using the coronal view.

RESULTS

Clinical outcomes significantly improved 1 year after surgery. The postoperative ACL length (29.7 ± 2.4 mm) and proximal angle (47.0 ± 7.4°) at 90° of knee flexion decreased relative to the preoperative values (31.5 ± 2.3 mm and 51.8 ± 8.7°, P < 0.01). The postoperative ACL inclination (64.9 ± 5.6°) at 10° of knee flexion decreased relative to the preoperative value (69.7 ± 5.6°, P < 0.01).

CONCLUSION

Pathologically-stretched linear ACL at 90° of knee flexion and a steep ACL inclination at 10° of knee flexion could be reduced after MM posterior root repair. This suggests that pullout repair could restore MM function as a secondary stabilizer, thereby preventing meniscal and cartilage degeneration.

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.

Posterior knee arthroscopy facilitates the safe and effective all-inside repair of locked bucket-handle medial meniscal tear using a suture hook technique

PURPOSE

This study reported the outcomes of locked bucket-handle medial meniscal tear (BHMMT) repairs using an arthroscopic posterior approach during anterior cruciate ligament (ACL) reconstruction.

METHODS

Between 2011 and 2014, 48 patients with BHMMTs and ACL tears who met the eligibility criteria were enrolled in the present study. BHMMTs were assessed using a posterolateral transseptal portal and repaired using a posteromedial portal. Transportal ACL reconstruction was performed using hamstrings autograft. Patients were assessed based on their IKDC and Lysholm scores and Tegner activity level. Meniscal healing was clinically evaluated based on the absence of swelling, joint line tenderness, locking, and catching; McMurray test results; and the need for meniscectomy.

RESULTS

According to follow-up assessments, the average IKDC and Lysholm scores improved significantly after 3-5 years (P < 0.001) CONCLUSION:  Excellent clinical outcomes were obtained when locked BHMMTs were repaired using an all-inside suture technique that employed posteromedial and posterolateral transseptal portals.

LEVEL OF EVIDENCE

IV.

Comparison of two simple stitches and modified Mason-Allen suture for medial meniscus posterior root tear based on the progression of meniscal posterior extrusion: A retrospective cohort study

Purpose: Medial meniscus (MM) posterior root (PR) tear leads to severe MM posterior extrusion (PE), resulting in rapid knee cartilage degeneration. MMPR repairs are recommended to reduce MMPE, especially during knee flexion. However, the difference in MMPE between different repair techniques remains unknown. This study aimed to investigate preoperative and postoperative MMPE following several pullout repair techniques. We hypothesized that a technique using two simple stitches (TSS) would be more useful than FasT-Fix-dependent modified Mason-Allen suture (F-MMA) to prevent the progression of MMPE in knee extension. Methods: This retrospective study included 35 patients who underwent MMPR repair. To compare MMPE, patients were divided into two groups according to the use of F-MMA while grasping the posterior capsule and TSS without grasping it. Open magnetic resonance imaging was performed at 10° and 90° knee flexion preoperatively, and at 3 and 12 months postoperatively, and the MMPE of both groups was evaluated. Results: A significant difference was observed between preoperative and 3-month postoperative MMPE at 90° knee flexion in both groups (p < .01). A significant difference was observed in 3- and 12-month postoperative MMPE at 10° knee flexion between both groups (p = .04/.02), whereas no significant difference in the preoperative MMPE at 10° knee flexion was observed between them (p = .45). Conclusions: Both repairs were found to be useful to reduce MMPE in knee flexion. Further, F-MMA repair increased MMPE in knee extension, unlike TSS repair. These findings suggest that TSS might have more advantages for load distribution when standing or walking.

[Clinical application of arthroscopic automatic reverse guide wire passer in posterior meniscus root reconstruction]

OBJECTIVE

To explore the application value and operation skills of arthroscopic automatic reverse guide wire passer (hereinafter referred to as wire passer) in the posterior meniscus root reconstruction.

METHODS

Between August 2015 and December 2020, 36 patients with posterior meniscus root tears were admitted. There were 16 males and 20 females, with an average age of 46 years (range, 26-66 years). There were 15 cases of sports injury and 21 cases of degenerative injury. The disease duration was 3-180 days, with a median of 28 days. The posterior root of the medial meniscus was injured in 29 cases, and the posterior root of the lateral meniscus was injured in 7 cases. The preoperative Lysholm score of the knee joint was 47.6±3.9, and the International Knee Score Committee (IKDC) score was 39.3±3.0. The meniscus was sutured by using wire passer under arthroscopy. During operation, the suture operation was evaluated according to the self-defined evaluation standard. Lysholm score and IKDC score were used to evaluate knee joint function.

RESULTS

All meniscuses were sutured successfully by using wire passer. The operation time of suture was 5-15 minutes, with an average of 10 minutes. According to the self-defined evaluation standard, the suture operation was scored as 0-10, with an average of 5. After operation, except for 2 cases of incision fat liquefaction, the incisions of the other patients healed by first intention. All patients were followed up 1-3 years, with an average of 1.5 years. The Lysholm score was 88.2±2.1 and the IKDC score was 51.7±2.3 at 1 year after operation, showing significant difference when compared with preoperative ones ( P<0.001). Fifteen cases underwent MRI re-examination, the results showed that the continuity and integrity of the posterior root had been restored.

CONCLUSION

Under arthroscopy, the wire passer for the posterior meniscus root reconstruction has the advantages of simple operation, reliable suture quality, and shorter operation time.

A posterior anchoring method decreases pullout suture translation of the medial meniscus posterior root repair during knee flexion

BACKGROUND

The medial meniscus (MM) translates posteriorly and extrudes severely from the medial tibial plateau (MTP) during knee flexion in the MM posterior root tear (PRT) knee. Transtibial pullout repair of the MMPRT has been performed to regulate MM extrusion. This study aimed to evaluate pullout suture translation during knee flexion before and after posterior anchoring during pullout repair. We hypothesized that suture translation after posterior anchoring would be significantly decreased relative to that before posterior anchoring.

METHODS

Thirty-five patients who underwent MM posterior root repair were prospectively investigated. Pullout repair was performed using two cinch sutures (outer and inner sutures) and posterior anchoring through the MM posterior horn and an additional bone tunnel on the MTP. The translation of the outer suture from 0° to 90° of knee flexion was measured and compared before and after posterior anchoring intraoperatively. The MM morphologic features were measured using preoperative magnetic resonance imaging, and the correlation between these values and outer suture translation was evaluated.

RESULTS

The average outer suture translation after posterior anchoring (1.6 ± 1.5 mm) was significantly decreased relative to that before posterior anchoring (2.5 ± 1.7 mm, P < 0.01). No significant correlations were observed between the MM morphological features and outer suture translation.

CONCLUSIONS

The posterior anchoring method with an MM posterior root repair is useful in decreasing posterior translation of the pullout suture during knee flexion, which might have an advantage in preventing suture pullout from the repaired MM, leading to good clinical outcomes.

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.

Accurate placement of a tibial tunnel significantly improves meniscal healing and clinical outcomes at 1 year after medial meniscus posterior root repair

PURPOSE

A medial meniscus posterior root tear results in the loss of meniscal circumferential hoop stress and causes a pathological posteromedial extrusion of the medial meniscus. Although creating a tibial tunnel in the anatomic place improves postoperative medial meniscus posterior extrusion, no studies have evaluated the relationship between tibial tunnel position and clinical outcomes. This study aimed to evaluate how tibial tunnel positioning of medial meniscus posterior root pullout repair affects meniscal healing status and clinical outcomes.

METHODS

Sixty-two patients with 64 medial meniscus posterior root tears (mean age 62.8 ± 7.9 years) who had undergone pullout repairs and second-look arthroscopies were included. All 62 patients were Lachman test negative. Three-dimensional computed tomography images of the tibial surface were evaluated using a rectangular measurement grid to assess the tibial tunnel centre and medial meniscus posterior root attachment centre. Spearman's rank correlation analysis was undertaken to determine displacement distance from the medial meniscus posterior root attachment centre to the tibial tunnel centre and a meniscal healing score, as well as clinical outcomes at 1 year post-repair.

RESULTS

Tibial tunnel centres were located more anteriorly and medially than the medial meniscus posterior root attachment centre (mean distance 5.0 ± 2.2 mm). The mean meniscal healing score was 6.7 ± 1.8 of 10 possible points. The 1-year postoperative clinical scores showed significant improvement compared with preoperative scores for all the items. There was a significant negative correlation in the absolute distance between the medial meniscus posterior root attachment centre and the tibial tunnel centre with the meniscal healing score (ρ =  - 0.39, p = 0.002). Furthermore, there were significant positive correlations between the distance between the medial meniscus posterior root attachment centre and the tibial tunnel centre in the mediolateral direction and patient-based clinical outcomes (ρ = 0.25-0.43, p < 0.05).

CONCLUSION

Accurate placement of a tibial tunnel, especially in the mediolateral direction, significantly improved meniscal healing and clinical outcomes at 1 year following medial meniscus posterior root repair. Surgeons should create a medial meniscus posterior root tibial tunnel at the anatomic attachment with particular attention to the mediolateral position.

LEVEL OF EVIDENCE

Level IV.

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.

A posterior shiny-corner lesion of the tibia is observed in the early phase after medial meniscus posterior root tear

BACKGROUNDS

Medial meniscus (MM) posterior root tear (PRT) results in joint overloading and degenerative changes in the knee, and pullout repair is recommended to prevent subsequent osteoarthritis. Diagnosing MMPRT is sometimes difficult, especially in the case of an incomplete tear. A posterior shiny-corner lesion (PSCL) is reported to be useful for diagnosis, although the association between MMPRT and PSCL is unknown. This study aimed to investigate the properties of PSCL, such as the location, volume, and duration from injury to the time of MRI (duration). We hypothesized that PSCL is observed in the early phase after the MMPRT onset.

METHODS

T2-weighted fat-suppression magnetic resonance imaging (MRI) was obtained from 55 patients with MMPRT preoperatively. The prevalence of the PSCL; giraffe neck, cleft, and ghost signs; severe MM extrusion (> 3 mm); and the PSCL volume were evaluated. The PSCL lesion elliptical volume (mm³) was calculated by measuring the anteroposterior, transverse, and craniocaudal dimensions.

RESULTS

PSCL was observed in 34 (62%) cases. The mean volume of the PSCL was 102.0 mm³. A significantly shorter duration was observed in the PSCL-positive group (5.6 weeks) than that in the PSCL-negative group (40.9 weeks, P < 0.01), although no significant correlation was observed between the PSCL volume and duration. The sensitivity for the MMPRT was 90.5% when the cut-off duration value was 3 weeks and 81.8% when the cut-off value was 8 weeks.

CONCLUSIONS

MRI examination may detect PSCL if it is performed early following MMPRT onset. Detecting PSCL may be useful in diagnosing MMPRT with high sensitivity.

Placement of an anatomic tibial tunnel significantly improves the medial meniscus posterior extrusion at 90° of knee flexion following medial meniscus posterior root pullout repair

PURPOSE

The purpose of this study was to evaluate the influence of tibial tunnel position in pullout repair for a medial meniscus (MM) posterior root tear (MMPRT) on postoperative MM extrusion.

METHODS

Thirty patients (median age 63 years, range 35-72 years) who underwent transtibial pullout repairs for MMPRTs were included. Three-dimensional computed tomography images of the tibial surface were evaluated using a rectangular measurement grid for assessment of tibial tunnel position and MM posterior root attachment. Preoperative and postoperative MM medial extrusion (MMME) and posterior extrusion (MMPE) at 10° and 90° knee flexion were measured using open magnetic resonance imaging.

RESULTS

Tibial tunnel centers were located more anteriorly and more medially than the anatomic center (median distance 5.8 mm, range 0-9.3 mm). The postoperative MMPE at 90° knee flexion was significantly reduced after pullout repair, although there was no significant reduction in MMME or MMPE at 10° knee flexion after surgery. In the correlation analysis of the displacement between the anatomic center to the tibial tunnel center and improvements in MMME, and MMPE at 10° and 90° knee flexion, there was a significant positive correlation between percentage distance and improvement of MMPE at 90° knee flexion.

CONCLUSION

This study demonstrated that the nearer the tibial tunnel position to the anatomic attachment of the MM posterior root, the more effective the reduction in MMPE at 90° knee flexion. Our results emphasize that an anatomic tibial tunnel should be created in the MM posterior root to improve the postoperative MMPE and protect the articular cartilage in a knee flexion position. Placement of an anatomic tibial tunnel significantly improves the MMPE at 90° of knee flexion after MM posterior root pullout repair.

LEVEL OF EVIDENCE

IV.

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.