BACKGROUND: This study aimed to examine whether the non-weight-bearing tunnel view X-ray is effective for short-term evaluation of medial meniscus posterior root tear (MMPRT) by assessing the X-ray characteristics at the initial and follow-up visits.
METHODS: This was a retrospective longitudinal study of 26 enrolled knees diagnosed with MMPRT on magnetic resonance imaging. The distance between the medial tibial eminence and medial femoral condyle (MTE-MFC distance) and medial tibiofemoral joint (MTFJ) width were measured by obtaining non-weight-bearing tunnel view and frontal view X-ray radiographs. The initial and follow-up values at a median interval of 17 days were compared. Additionally, the correlations between the MTE-MFC distance increase rate and body mass index (BMI), age, femorotibial angle (FTA), and posterior tibial slope (PTS) were evaluated using linear regression analysis.
RESULTS: The tunnel view images of the initial and follow-up X-rays showed a significant increase in the MTE-MFC distance and a significant decrease in the MTFJ width. Furthermore, a moderate correlation was observed between the change in the MTE-MFC distance and the time interval between X-rays. However, no substantial correlation was observed for the change in the MTFJ width over time. Moreover, no significant correlation was observed between the change in the MTE-MFC distance in the non-weight-bearing tunnel view and BMI, age, FTA, and PTS.
CONCLUSIONS: The non-weight-bearing tunnel view is highly beneficial for evaluating MMPRT progression in the short term.

OBJECTIVE: We describe 13 cases of medial meniscus posterior root tear (MMPRT) with varus knee alignment treated with medial meniscus posterior root reconstruction (MMPR-R) and open-wedge high-tibial osteotomy (OWHTO) to identify an optimal MMPRT treatment.
METHODS: We retrospectively reviewed 13 patients (mean age: 66.3 ± 8.0 years) who underwent MMPR-R and OWHTO. The Knee Injury and Osteoarthritis Outcome Score (KOOS), femorotibial angle (FTA), percentage mechanical axis (%MA) on radiography, and medial meniscus extrusion (MME) on magnetic resonance imaging (MRI) between the preoperative period and last follow-up were compared. Moreover, meniscus healing status and the International Cartilage Repair Society (ICRS) classification of the medial femoral condyle and medial tibial plateau on arthroscopy between the initial surgery and second-look arthroscopy were compared.
RESULTS: The mean follow-up duration was 12.8 ± 2.2 months. At the last follow-up, the KOOS significantly improved (P < 0.01). Based on the FTA and %MA, the varus alignment was predominantly corrected at the last follow-up (P < 0.01). The MME was increased in nine (62.9%) patients, and the mean MME significantly increased at the last follow-up (P = 0.04). Second-look arthroscopy revealed improvements in the ICRS grade for the medial femoral condyle and medial tibial plateau in six (46.2%) patients. However, the results did not significantly differ. Regarding meniscus healing, four (30.8%) patients presented with complete healing, eight (57.1%) with partial healing, and one (7.7%) with failed healing.
CONCLUSIONS: The MMPRT with varus knee alignment significantly improved with MMPR-R and OWHTO. However, the MME and meniscus healing were unsatisfactory.

UNASSIGNED: 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.
UNASSIGNED: To describe a subpopulation of patients with traumatic MMPRT.
UNASSIGNED: Systematic review; Level of evidence, 5.
UNASSIGNED: 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.
UNASSIGNED: 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%).
UNASSIGNED: 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.

UNASSIGNED: To summarize the current research progress on the concept, clinical presentation, diagnosis, biomechanical changes, and pathological mechanisms of the medial meniscus posterior root tear (MMPRT), and its clinical correlations with tibial rotation.
UNASSIGNED: The research literature on MMPRT and its relationship with tibial rotation at home and abroad in recent years was extensively consulted and summarized.
UNASSIGNED: MMPRT is a specific and common type of medial meniscus injury of the knee joint. The occurrence of posterior medial pumping pain events following low-energy trauma in patients provides important clues for the diagnosis of this injury, with MRI being the preferred imaging modality. The biomechanical effects generated by MMPRT are similar to those caused by total removal of the medial meniscus. And this injury is usually associated with tibial rotation. MMPRT induces pathological external rotation of the tibia, which can be restored by timely medial meniscus posterior root repair. Furthermore, changes in tibial rotation are related to the healing status after medial meniscus posterior root repair.
UNASSIGNED: MMPRT is closely related to tibial rotation. Understanding the biomechanics, pathological mechanisms, and clinical correlations between the two is of great significance for improving the diagnosis and treatment strategies.
UNASSIGNED: 总结目前关于内侧半月板后根部撕裂（medial meniscus posterior root tear，MMPRT）的概念、临床表现、诊断、生物力学变化、病理机制及其与胫骨旋转关系的临床关联性研究进展。.
UNASSIGNED: 广泛查阅近年来国内外关于MMPRT及其与胫骨旋转关系的研究文献，并进行总结分析。.
UNASSIGNED: MMPRT是膝关节内侧半月板损伤的一种特殊且常见类型，患者在低能量损伤后出现的膝关节后内侧爆裂疼痛事件对其诊断具有重要提示。MRI是首选影像学检查方式。MMPRT产生的生物力学效应类似于内侧半月板全部切除，且该损伤通常与胫骨旋转有关，MMPRT诱发了胫骨的病理性外旋，及时修复内侧半月板后根能够恢复这种病理性外旋。同时，胫骨旋转的变化与内侧半月板后根修复后的愈合状态相关。.
UNASSIGNED: MMPRT与胫骨旋转密切相关，了解二者间的生物力学、病理机制和临床关联性，对于改善MMPRT的诊断和治疗策略具有重要意义。.

UNASSIGNED: 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.
UNASSIGNED: 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.
UNASSIGNED: Meta-analysis; Level of evidence, 4.
UNASSIGNED: 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.
UNASSIGNED: 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.
UNASSIGNED: 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.

UNASSIGNED: To evaluate the technique of transtibial pull-out repair with tibial interference screw fixation for medial meniscus posterior root (MMPR) tear by reporting on short-term outcomes and complications.
UNASSIGNED: All MMPR repairs performed between January 2019 and August 2021 (n = 70) were retrospectively screened regarding demographic data and surgical parameters. The patients were questioned for performed revision surgery, symptoms and complications. The Numeric Rating Scale (NRS) for pain, Lysholm Knee Score and International Knee Documentation Committee Subjective Knee Form (IKDC) questionnaires were used to evaluate clinical outcome. In cases of revision surgery for re-tear the mode of failure was intraoperatively classified (patients with re-tear were excluded from the clinical follow-up examination). The influence of demographic and treatment parameters (surgical and rehabilitation) on the incidence and mode of re-tear and clinical scores was evaluated.
UNASSIGNED: After 2.3 ± 0.7 years, 62 patients (88.6 %) were available for follow-up. There were no direct intra- or postoperative complications. No revision was performed due to symptoms related to the tibial fixation material. The mean surgery time was 33.5 ± 10.8 min. The overall re-tear rate was 17.7 % (11 patients) of whom 10 were treated surgically and one conservatively. Primary mode of failure was suture cut-out from the meniscus (70 %). The NRS, Lysholm Knee Score and subjective IKDC were obtained in 38 patients and improved from 6.8 ± 2.4, 40.1 ± 23.9 and 32.8 ± 16.3 to 2.2 ± 2.2, 80.5 ± 16.3 and 63.0 ± 13.9, respectively (all p < 0.001). No influence was observed from demographic and treatment parameters on re-tear rates or clinical Scores.
UNASSIGNED: Tibial interference screw fixation is a fast and promising technique for MMPR transtibial pull-out repair. In the presented technique, utilizing non-absorbable locking sutures alongside tibial interfenrence screw fixation, the primary mode of failure was suture cut-out from the meniscus.

OBJECTIVE: This retrospective study aimed to investigate the relationship between intercondylar notch width (ICNW), osteophyte width (OW), and the healing of medial meniscus posterior root tears (MMPRTs) following arthroscopic pullout repair.
METHODS: The study included 155 patients diagnosed with MMPRTs who underwent transtibial pullout repair. Meniscal healing status was evaluated on second-look arthroscopy using a previously reported meniscus healing score. Patients were divided into two groups based on this score: the high healing score (group HH, healing score ≥ 8 points) and suboptimal healing score (group SO, healing score ≤ 6 points) groups. Computed tomography scans were performed on patients 1 week postsurgery. ICNW and OW widths were measured and relatively evaluated based on their ratio to the intercondylar distance (ICD), represented as the ICNW/ICD ratio (%) and OW/ICD ratio (%), respectively. Patient-reported outcomes were assessed preoperatively and on second-look arthroscopy using the Knee injury and Osteoarthritis Outcome Score (KOOS) and visual analogue scale (VAS).
RESULTS: There were no significant demographic differences between the SO and HH group (n = 35 and 120 patients, respectively). Regarding radiographic measurements, significant differences were observed in the ICNW/ICD ratio (group SO, 24.2%; group HH, 25.2%; p = 0.024), OW (group SO, 2.6 mm; group HH, 2.0 mm; p < 0.001), and OW/ICD ratio (group SO, 3.5%; group HH, 2.7%; p < 0.001). Both groups had similar preoperative clinical scores, but postoperative clinical scores, including KOOS-activities of daily living (group SO, 83.4; group HH, 88.7; p = 0.035) and VAS (group SO, 19.1; group HH, 11.3; p = 0.005), were significantly better in group HH.
CONCLUSIONS: The study suggests that ICNW and OW may play a crucial role in MMPRT healing following arthroscopic pullout repair, as evidenced by the worse clinical outcomes associated with a narrower ICNW and wider OW. These findings highlight the potential significance of ICNW and OW assessments when evaluating meniscal repair indications.
METHODS: Level III.

Objective The aim of this study is to compare preoperative and postoperative radiological results in knees with medial meniscus posterior root tears (MMPRT) and varus alignment, with a particular emphasis on medial meniscal extrusion (MME), following high tibial osteotomy (HTO) without root repair. Method Patients who underwent open wedge HTO for medial compartment osteoarthritis between January 2015 and December 2020 were retrospectively reviewed. The inclusion criteria were defined as patients with preoperative and postoperative magnetic resonance imaging (MRI) and weight-bearing radiographs including radiological images of the entire lower extremity. After conducting data screenings, patients diagnosed with a preoperative MMPRT were included in the study. Patients underwent measurements of medial proximal tibial angle (MPTA), mechanical lateral distal femoral angle (mLDFA), and mechanical axis deviation (MAD) on anteroposterior radiographs encompassing the entire lower extremity during the preoperative and postoperative first year. In order to determine the degree of arthritis, The Kellgren-Lawrence (KL) grading system was employed on preoperative and the most recent anteroposterior knee radiographs of the patients. MME, the distance (in millimeters) between the peripheral border of the meniscus body (meniscocapsular junction) and the medial border of the tibial plateau, was measured and calculated on coronal MRI. Preoperative and postoperative measurements of MPTA, MAD, MME, and KL staging were compared. Results The study included a total of 21 patients, comprising 7 males and 14 females. Among these, 6 were left-sided and 15 were right-sided cases, with an average age of 52.2 (±6.1) years. The mean follow-up duration for the patients was 5.4 (±2.3) years, with an average time of 2.2 (±1.6) years from surgery to the MRI. While significant differences were observed between preoperative and postoperative measurements for MAD and MPTA (p <0.01), no significant difference was found in MME measurement (p: 0.507). Pearson correlation analysis was employed to determine the correlation between preoperative and postoperative values of MME, MPTA, and MAD. A significant negative correlation was observed between preoperative MME and MPTA (r: -0.464, p:0.034). No significant correlation was found between postoperative MME and MAD or MPTA. Comparisons based on KL staging between the preoperative and postoperative periods did not reveal any significant differences (p: 0.525). Conclusion In knees with both MMPRT and varus alignment, our study demonstrated that postoperative MME and radiological progression of arthritis did not increase after HTO without MMPRT repair. These findings suggest that HTO treatment performed without MMPRT repair may prevent an increase in MME and the progression of arthritis. According to the results of our study, we observed a negative correlation between MME and MPTA during the preoperative period, which supports the relationship between varus deformity and MME.

OBJECTIVE: This study aimed to determine whether the repair of a medial meniscus posterior root tear (MMPRT) is effective for MMPRT healing, cartilage regeneration, and clinical outcomes in opening wedge high tibial osteotomy (OWHTO).
METHODS: This retrospective study included 80 patients who underwent OWHTO and subsequent second-look arthroscopy. The patients were divided into OWHTO-with-MMPRT-repair (n = 40) and OWHTO alone (n = 40) groups, and the healing rates (complete/partial/failure) were compared. Each group was further divided into over- and under-corrected subgroups to compare healing rates. The International Cartilage Repair Society (ICRS) grade, cartilage defect size, Koshino stage, ICRS cartilage repair assessment score of the medial femoral condyle (MFC), and International Knee Documentation Committee (IKDC) scores between the OWHTO-with-MMPRT-repair and OWHTO alone groups were compared according to whether microfracture was performed on the MFC.
RESULTS: The overall healing rate of the MMPRT was higher in the OWHTO-with-MMPRT-repair group than that in the OWHTO alone group (P < 0.001). In addition, in the subgroup analysis, no difference in the MMPRT healing rate between the over-correction and under-correction groups when MMPRT repair was performed (n.s). In contrast, without MMPRT repair, the healing rate was lower in the under-correction group than that in the over-correction group (P = 0.03). Cartilage regeneration of the OWHTO-with-MMPRT-repair group was superior to that of the OWHTO alone group (P < 0.05). The IKDC subjective scores of the OWHTO-with-MMPRT-repair and OWHTO alone groups were 34.5 and 33.1 before surgery (n.s) and 50 and 47.2 at one year after surgery, respectively (n.s). These differences between the two groups for cartilage regeneration and IKDC subjective scores showed the same pattern regardless of microfractures.
CONCLUSIONS: MMPRT repair during OWHTO might improve MMPRT healing, even with under-correction, and cartilage regeneration of MFC, regardless of microfracture. However, OWHTO with MMPRT repair might not improve short-term clinical outcomes compared to OWHTO alone. Further randomized clinical trials are necessary.
METHODS: III, Retrospective cohort study.

OBJECTIVE: To describe the patient-reported clinical outcomes following medial meniscus root repair with meniscus centralization and to identify common complications and detail provisional results.
METHODS: Patients undergoing medial meniscus root repair with meniscus centralization from 2020 to 2022 were identified using an institutional database. Patients were followed prospectively using postoperative Tegner Activity Scale, visual analog scale (VAS) for pain, Knee Injury and Osteoarthritis Outcome Score, Joint Replacement, International Knee Documentation Committee score, and a Likert score for improvement, surgery satisfaction, and subsequent surgeries at minimum 1-year follow-up with mean 2-year follow-up. Demographics, injury characteristics, and surgical details were also collected.
RESULTS: Twenty-five patients (age: 50 ± 11 years; sex: 76% female; body mass index: 33 ± 8) were included in this study. Postoperative Tegner score was maintained at preoperative levels (P = .233), and VAS at rest, VAS with use, Knee Injury and Osteoarthritis Outcome Score, Joint Replacement, and International Knee Documentation Committee improved significantly postoperatively (P = .003; P < .001, P < .001, P = .023, respectively). Eighty-eight percent of patients reported subjective improvement in their knee at final follow-up. Postoperative radiographs did not show any significant osteoarthritis progression, and no patients had undergone a revision meniscus surgery or total knee arthroplasty at the time of follow-up.
CONCLUSIONS: At minimum 1-year follow-up and mean 2-year follow-up, patients undergoing medial meniscus root repair with meniscus centralization demonstrated significant postoperative improvements in pain, function, and quality of life and reported high rates of surgery satisfaction. There was no evidence of significant arthritic progression on postoperative imaging, and no patients underwent revision meniscus surgery or total knee arthroplasty.
METHODS: Level IV, case series.