-
Medicina (Kaunas, Lithuania) Jun 2023Medial 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... (Review)
Review
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.
Topics: Humans; Menisci, Tibial; Knee Joint; Tibia; Rupture
PubMed: 37511993
DOI: 10.3390/medicina59071181 -
Osteoarthritis and Cartilage Sep 2007To evaluate anterior cruciate ligament transection (ACLT) and destabilization of the medial meniscus (DMM) surgical instability models of osteoarthritis (OA) in the...
OBJECTIVE
To evaluate anterior cruciate ligament transection (ACLT) and destabilization of the medial meniscus (DMM) surgical instability models of osteoarthritis (OA) in the 129/SvEv mouse knee joint.
DESIGN
Micro-surgical techniques were used to perform ACLT or DMM under direct visualization. Histological scoring was performed on multiple sections to assess cartilage damage across the entire joint.
RESULTS
The ACLT model gave severe OA, chondrogenesis of the joint capsule and, in some cases, severe subchondral erosion of the posterior tibial plateau. Surgical DMM was less invasive than the ACLT procedure and resulted in lesions primarily on the central weight-bearing region of the medial tibial plateau and medial femoral condyles. Lesions in the DMM model progressed from mild-to-moderate OA at 4 weeks, to moderate-to-severe OA at 8 weeks post-surgery. Destruction of the subchondral bone was never observed in the DMM model.
CONCLUSIONS
ACLT is not recommended in the mouse due to the high surgical proficiency required and the development of severe OA that may involve subchondral bone erosion. The severity and location of lesions following DMM are consistent with lesions observed in aged spontaneous mouse models of OA. The DMM model has sufficient sensitivity to show disease modification, as observed with the ADAMTS-5 knock out (KO) mouse. The DMM model should be a first choice to challenge mice with gene deletions of potential targets in OA.
Topics: Animals; Anterior Cruciate Ligament; Disease Models, Animal; Disease Progression; Feasibility Studies; Menisci, Tibial; Mice; Mice, Mutant Strains; Osteoarthritis
PubMed: 17470400
DOI: 10.1016/j.joca.2007.03.006 -
Arthroscopy : the Journal of... Sep 2003A discoid medial meniscus is an extremely rare anomaly. We present 4 cases of symptomatic discoid medial meniscus. Furthermore, magnetic resonance imaging (MRI) of the... (Review)
Review
A discoid medial meniscus is an extremely rare anomaly. We present 4 cases of symptomatic discoid medial meniscus. Furthermore, magnetic resonance imaging (MRI) of the unaffected knee was obtained in 3 cases, and 1 patient had bilateral discoid medial menisci as well as a unilateral discoid lateral meniscus proven by MRI. Another patient had bilateral discoid medial menisci. In one of the other 2 cases, an MRI of the unaffected knee was not obtained. However, in the involved knees of both cases, medial and lateral menisci were discoid. The incidence of bilateral discoid medial menisci is unknown. In the past, the diagnosis of a discoid meniscus was made with an arthrogram or at arthrotomy. Therefore, whether some of the unilateral cases reported in the literature might have been bilateral is unknown. The reported prevalence of bilateral discoid medial menisci will probably increase, because when a discoid medial meniscus is encountered currently, an MRI is used to find knee disorders, including in the contralateral knee. Axial multiplanar gradient-recalled-echo imaging could provide images of the discoid meniscus, depicted in its entirety in one section. This would make the recognition of a discoid meniscus simple.
Topics: Abnormalities, Multiple; Adult; Arthroscopy; Exostoses; Female; Humans; Magnetic Resonance Imaging; Male; Menisci, Tibial; Middle Aged; Pain; Tibial Meniscus Injuries
PubMed: 12966402
DOI: 10.1016/s0749-8063(03)00688-1 -
The Journal of the American Academy of... May 2009Avulsion of the posterior horn of the medial meniscus can occur from acute trauma or chronic degeneration, leading to meniscus extrusion, articular cartilage loss,... (Review)
Review
Avulsion of the posterior horn of the medial meniscus can occur from acute trauma or chronic degeneration, leading to meniscus extrusion, articular cartilage loss, osteophyte formation, and medial joint space narrowing. With meniscus extrusion, the meniscus is unable to resist hoop stresses and cannot shield the adjacent articular cartilage from excessive axial load. Over time, this can lead to symptomatic knee osteoarthritis. Patients typically report pain, swelling, mechanical symptoms, and general functional loss. Although nonsurgical care may relieve symptoms, it is unlikely to alter either the natural history of meniscal loss or the fate of the medial compartment. Surgical repair of posterior horn meniscal avulsion is done in an attempt to restore the anatomy and biomechanical function of the meniscus, and to slow or prevent degenerative joint disease. Meniscal transplantation is reserved for salvage situations.
Topics: Biomechanical Phenomena; Diagnostic Imaging; Humans; Joint Diseases; Knee Injuries; Menisci, Tibial; Orthopedic Procedures; Tibial Meniscus Injuries
PubMed: 19411639
DOI: 10.5435/00124635-200905000-00002 -
Journal of Orthopaedic Surgery (Hong... 2023Complete meniscus root tear is associated with meniscus extrusion; this causes a loss of meniscus function and accelerated osteoarthritis of the knee. Existing... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Complete meniscus root tear is associated with meniscus extrusion; this causes a loss of meniscus function and accelerated osteoarthritis of the knee. Existing small-scale retrospective case-control studies suggested that the outcomes were different between medial and lateral meniscus root repair. This meta-analysis aims to study whether such discrepancies exist via a systematic review of the available evidence in the literature.
METHODS
Studies evaluating the outcomes of surgical repair of posterior meniscus root tears, with reassessment MRI or second-look arthroscopy, were identified through a systematic search of PubMed, Embase, and Cochrane Library. The degree of meniscus extrusion, healing status of the repaired meniscus root, and functional outcome scores after repair were the outcomes of interest.
RESULTS
Among the 732 studies identified, 20 studies were included in this systematic review. 624 knees and 122 knees underwent MMPRT and LMPRT repair, respectively. The amount of meniscus extrusion following MMPRT repair was 3.8 ± 1.7 mm, which was significantly larger than the 0.9 ± 1.2 mm observed after LMPRT repair ( < 0.001). Significantly better healing outcomes were observed on reassessment MRI after LMPRT repair ( < 0.001). The postoperative Lysholm score and IKDC score was also significantly better after LMPRT than MMPRT repair ( < 0.001).
CONCLUSIONS
LMPRT repairs resulted in significantly less meniscus extrusion, substantially better healing outcomes on MRI, and superior Lysholm/IKDC scores, when compared to MMPRT repair. This is the first meta-analysis we are aware of that systematically reviews the differences in the clinical, radiographic, and arthroscopic results of MMPRT and LMPRT repair.
Topics: Humans; Menisci, Tibial; Retrospective Studies; Knee Joint; Osteoarthritis; Magnetic Resonance Imaging; Arthroscopy; Rupture
PubMed: 37173149
DOI: 10.1177/10225536231175233 -
Knee Surgery, Sports Traumatology,... Aug 2023Medial meniscus extrusion (MME) refers to the protrusion of the medial meniscus beyond the tibial edge by more than 3 mm, leading to a deficiency of the hoop strain.... (Meta-Analysis)
Meta-Analysis Review
Radiographic OA, bone marrow lesions, higher body mass index and medial meniscal root tears are significantly associated with medial meniscus extrusion with OA or medial meniscal tears: a systematic review and meta-analysis.
PURPOSE
Medial meniscus extrusion (MME) refers to the protrusion of the medial meniscus beyond the tibial edge by more than 3 mm, leading to a deficiency of the hoop strain. MME commonly occurs in conjunction with osteoarthritis (OA) or medial meniscal tears (MMT). However, factors associated with concomitant MME in patients with OA or MMT have not been systematically reviewed. This study aims to perform a systematic review and meta-analysis to identify factors associated with concomitant MME in OA or MMT.
METHODS
The systematic review of the literature was performed according to PRISMA. A literature search was conducted in 4 databases. All original human studies that reported the available evidence on factors associated with concomitant MME in patients with OA or MMT were included. Pooled binary variables were analyzed by odds ratios (OR) and 95% CIs, and pooled continuous variables were evaluated by mean difference (MD) and 95% CIs.
RESULTS
Ten studies on OA (5993 patients) and eight studies on MMT (872 patients) met the inclusion criteria. The overall pooled incidence of MME was 43% (95% CI, 37-50%) for OA, 61% (95% CI 43-77%) for MMT, and 85% (95% CI 72-94%) for medial meniscal root tears (MMRT). For the population with OA, Factors significantly associated with MME included radiographic OA [OR 4.24; 95% CI 3.07-5.84; P < 0.0001], bone marrow lesions [OR, 3.35; 95% CI 1.61-6.99; P = 0.0013], cartilage damage [OR, 3.25; 95% CI 1.60-6.61; P = 0.0011], and higher body mass index (BMI) [MD, 1.81; 95% CI 1.15-2.48; P < 0.0001]. Factors strongly associated with increased risk of MME for MMT included medial meniscal root [OR, 8.39; 95% CI 2.84-24.82; P < 0.0001] and radial tears [OR, 2.64; 95% CI 1.18-5.92; P < 0.0001].
CONCLUSION
Radiographic OA, bone marrow lesions, cartilage damage, and higher BMI were significantly associated with concomitant MME with OA. Furthermore, medial meniscal root and radial tears were significantly associated with an increased risk of MME in patients with MMT.
LEVEL OF EVIDENCE
IV.
Topics: Humans; Menisci, Tibial; Body Mass Index; Bone Marrow; Retrospective Studies; Magnetic Resonance Imaging; Osteoarthritis; Cartilage Diseases; Bone Diseases
PubMed: 37099153
DOI: 10.1007/s00167-023-07418-8 -
The American Journal of Sports Medicine Feb 2021
Topics: Humans; Knee Injuries; Meniscectomy; Menisci, Tibial; Rupture; Tibial Meniscus Injuries
PubMed: 33523755
DOI: 10.1177/0363546520982988 -
Orthopaedic Surgery Sep 2022Complete discoid medial meniscus is an extremely rare abnormality of the knee joint whose meniscus has a discoid shape rather than a normal semilunar one. Several medial... (Review)
Review
BACKGROUND
Complete discoid medial meniscus is an extremely rare abnormality of the knee joint whose meniscus has a discoid shape rather than a normal semilunar one. Several medial meniscus anomalies including anomalous insertion have been reported in the literature. This report presents a rare case of symptomatic complete discoid medial meniscus whose anterolateral (apical) portion was completely coalesced with the ACL. MRI, radiographic, and arthroscopic findings in the medial compartment are to be submitted.
CASE PRESENTATION
A 29-year-old male presented with intermittent pain and swelling of the right knee for 2 years. Based on radiographic, MRI, and physical examination findings, he was diagnosed with discoid medial meniscus tears. Arthroscopic saucerization was performed for the torn discoid medial meniscus of the right knee. Arthroscopic examination revealed a complete discoid medial meniscus and the anterolateral (apical) portion of which was completely coalesced with the ACL. Careful Probing of the meniscal surface revealed there was a longitudinal tear extending from the tibial spine to the midportion of the meniscus. Arthroscopic saucerization of the discoid meniscus was performed after closely cutting the meniscus around the ACL. The patient reported no symptoms, and he had returned to his daily and sports activities, including football, basketball, and jogging, at the 12-month follow-up.
CONCLUSION
Complete discoid medial meniscus is an extremely rare abnormality, and this case presents the third complete discoid medial meniscus whose anterolateral (apical) portion was completely coalesced with the ACL. The current case we present strongly supports the hypothesis that ACL and meniscus were differentiated from the same mesenchyme.
Topics: Adult; Anterior Cruciate Ligament; Anterior Cruciate Ligament Injuries; Arthroscopy; Humans; Joint Diseases; Knee Joint; Magnetic Resonance Imaging; Male; Menisci, Tibial
PubMed: 35913195
DOI: 10.1111/os.13377 -
The Knee Jun 2022Spontaneous osteonecrosis of the knee (SONK) causes acute atraumatic knee pain, and meniscus tears may be associated with the pathogenesis of SONK. The purpose of this...
PURPOSE
Spontaneous osteonecrosis of the knee (SONK) causes acute atraumatic knee pain, and meniscus tears may be associated with the pathogenesis of SONK. The purpose of this study was to investigate the relationship of the type of meniscus tear and medial meniscus extrusion with SONK on the medial femoral condyle in patients who underwent surgical treatment with high tibial osteotomy due to severe knee pain.
METHODS
We enrolled 98 patients with 102 knees who underwent medial opening wedge high tibial osteotomy (OWHTO) under the diagnosis of medial femoral condyle osteonecrosis at our hospital from December 2003 to January 2020. Based on the Koshino classification, cases of SONK were classified as stage 1-4. The relationships of demographic data, X-rays and MRI images, including femorotibial angle (FTA), meniscus tear type, and medial meniscus extrusion (MME), with the stage and volume of SONK were investigated.
RESULTS
Ninety-eight patients (29 males and 69 females), with an average age at surgery of 69.2 ± 9.6 years and Body mass index(BMI) of 61.0 ± 17.6 kg/m. In 102 cases of SONK, 11 knees, 18 knees, 46 knees, and 27 knees were classified as stage 1-4, respectively. The mean SONK volume was 2161.61 µm (range 95.67-7484.68 µm) on preoperative MRI. The preoperative FTA (mean 180.86°, range 172-187°) was not associated with the stage or volume of SONK. Meniscus tears were found in all cases of SONK and consisted of 2 degenerations, 2 horizontal tears, 0 vertical tears, 40 radial tears, 4 complex tears, and 54 medial meniscus posterior root tears (MMPRTs). In addition, 99% (101/102) of knees showed more than 3 mm of meniscus extrusion. Although the meniscus tear type was not associated with SONK stage, there was a high rate of tears that caused disruption of the hoop strain, such as MMPRTs (52.9%) or radial tears (39.2%). MME was significantly related to SONK volume (r = 0.387, p < 0.001).
CONCLUSION
All patients with SONK had coexisting meniscus tears, most menisci had medial extrusion, and a positive correlation was observed between MME and SONK volume.
Topics: Female; Humans; Knee Joint; Magnetic Resonance Imaging; Male; Menisci, Tibial; Osteonecrosis; Osteotomy; Pain; Retrospective Studies; Tibial Meniscus Injuries
PubMed: 35533576
DOI: 10.1016/j.knee.2022.04.011 -
Australasian Radiology Aug 2006The posterior root attachment of the medial meniscus is readily identifiable on MRI. Unless specifically reviewed, injuries involving this structure may be overlooked.... (Review)
Review
The posterior root attachment of the medial meniscus is readily identifiable on MRI. Unless specifically reviewed, injuries involving this structure may be overlooked. Significant meniscal root pathology may cause functional incompetence of the meniscus, with consequent early onset cartilage degeneration and osteoarthritis. This review article emphasizes the importance of positive identification of an intact meniscal root and illustrates the known association of meniscal root injury or tear with medial extrusion of the medial meniscus by greater than 3 mm beyond the joint margin.
Topics: Cartilage Diseases; Humans; Knee Injuries; Magnetic Resonance Imaging; Menisci, Tibial; Tibial Meniscus Injuries
PubMed: 16884414
DOI: 10.1111/j.1440-1673.2006.01586.x