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.

Meniscal Extrusion: A Narrative Review

Background: Meniscal extrusion, referred to as an external displacement of the meniscus, is a commonly encountered but often overlooked magnetic resonance imaging finding in the knee joint. Meniscal extrusion alters the biomechanical properties of the meniscus, leading to accelerated cartilage degeneration and early osteoarthritic changes. The literature contains discrepancies about meniscal extrusion on topics ranging from definition to diagnosis. This narrative review outlines the pathogenesis, natural history, diagnosis, and treatment of meniscal extrusion. Purpose: To review the current literature on meniscal extrusion, from pathogenesis to treatment, and to provide recommendations for future research. Study Design: Narrative review. Methods: A computer-based search of the PubMed, Ovid Medline, and Cochrane Library databases was used to perform a comprehensive literature review on meniscal extrusion. A total of 81 studies was ultimately included in the review. Results: The literature review highlighted the current ambiguity in definition, difficulty in clinical diagnosis, and low level of awareness of this condition. This review covers all aspects related to meniscal extrusion and identifies many of its lesser known aspects. Conclusion: In the current literature, meniscal extrusion remains a lesser known albeit common condition because of its relatively silent nature along with lack of knowledge among orthopaedic surgeons. Further studies are warranted to provide better understanding and management of this condition.

Kinematic Analysis of Lateral Meniscal Oblique Radial Tears in the Anterior Cruciate Ligament–Deficient Knee

Background: Lateral meniscal oblique radial tears (LMORT) occur frequently in conjunction with anterior cruciate ligament (ACL) disruption and are anatomically distinct from meniscus root tears. Hypothesis/Purpose: The purpose of this study was to characterize the effects of LMORT types 3 (LMORT3) and 4 (LMORT4) lesions on joint stability and meniscal extrusion in ACL-deficient knees. Our hypothesis was that both lesions would promote significant increases in anterior translation and meniscal extrusion, with the LMORT4 lesion having a greater effect. Study Design: Controlled laboratory study. Methods: Two matched pairs of cadaveric knees (n = 4) were used to optimize the testing sequence. Additional cadaveric knees with LMORT3 (n = 8) and LMORT4 (n = 8) lesions created after ACL transection underwent robotic kinematic testing for anterior drawer and pivot-shift simulations with associated ultrasound-measured meniscal extrusion at clinically relevant knee flexion angles. Results: Optimization testing showed no differences on the effect of LMORT4 lesions for anterior translation and lateral meniscal extrusion with ACL-intact versus ACL-deficient knees. ACL deficiency and LMORT3 and LMORT4 lesions with ACL deficiency were associated with significantly greater anterior translation compared with ACL-intact state for both anterior drawer and pivot-shift testing at all flexion angles ( P < .001). ACL deficiency with either LMORT3 or LMORT4 lesion was associated with significantly greater anterior translation than was ACL deficiency only ( P < .005) for anterior drawer testing at 90° of flexion. Meniscal extrusion was greater with LMORT3 and LMORT4 lesions compared with ACL deficiency only ( P < .05) for anterior drawer at 60° of flexion and for pivot shift at 15° of flexion. The LMORT4 lesion demonstrated increased anterior translation for anterior drawer ( P = .003) at 60° of flexion (12%) as well as for pivot shift at 15° of flexion (7%) and 30° of flexion (13%) ( P < .005) compared with ACL deficiency only. Conclusion: In this cadaveric model, the addition of an LMORT3 or LMORT4 lesion increased anterior laxity for both the anterior drawer and the pivot shift when compared with an isolated ACL tear. Lateral meniscal extrusion was also exacerbated by these LMORT lesions. Clinical Relevance: LMORT lesions, distinct from meniscus root tears, occur frequently in conjunction with ACL tears. This study characterized the biomechanical consequences of LMORT3 and LMORT4 lesions on joint stability and meniscal function, highlighting the importance of diagnosing and treating LMORT lesions at the time of ACL reconstruction.

Usefulness of ultrasonography for dynamic evaluation of medial meniscus hoop function in early knee osteoarthritis

This study aimed to evaluate the dynamics of the medial meniscus during knee flexion–extension by ultrasonography and compare them with MRI findings to confirm the usefulness of ultrasonography for evaluating early knee osteoarthritis (KOA). In total, 100 patients were diagnosed with early KOA using clinical and radiographical findings. Dynamic ultrasonographic evaluation and MRI were performed in all patients. Medial meniscal extrusion (MME) and medial meniscal tears were evaluated via ultrasonography and MRI. Abnormal MME was defined as MME > 2 mm on ultrasonography during knee extension. Patients with abnormal MME were divided into two groups: a decrease group (group D) and a non-decrease group (group N). Age, sex, absence or type of meniscus tear, and MME were compared between the two groups. Of the 100 patients, 75 demonstrated MME > 2 mm at knee extension. MME at all assessment positions using ultrasonography and MRI were significantly greater in group N (n = 34) than that in group D (n = 41). Medial meniscus posterior root tears or radial tears were observed in most cases in group N. A lack of decrease in MME from 0° to 90° of flexion on ultrasonography was a characteristic finding in patients with a loss of meniscal hoop function.

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

Background: Meniscus root tears (MRTs) are defined as radial tears within 1 cm of the meniscus root insertion or an avulsion of the meniscus root itself. They lead to altered joint loading because of the failure to convert axial (compressive) loads into hoop stresses. Untreated MRTs can result in altered joint biomechanics and accelerated articular cartilage degeneration and the development of osteoarthritis (OA), yet optimal management remains unclear. Purpose: To review treatment outcomes after acute MRTs by surgical repair, debridement, meniscectomy, or nonoperative treatment. Design: Systematic review; Level of evidence, 4. Methods: A systematic review of the evidence from human clinical studies was conducted with electronic searches of the PUBMED, Medline, EMBASE, and the Cochrane Library databases. One reviewer extracted the data and 2 reviewers assessed the risk of bias and performed synthesis of the evidence. Results: Eleven studies of low to moderate methodological quality were identified. All treatment options improved functional scores after >12 months. Arthroscopic repair may be associated with better functional outcomes when compared with partial meniscectomy and nonoperative management at 12-month follow-up. Radiographic progression of OA occurred in all treatment groups; there was some evidence that this was delayed after repair when compared with other treatments. Baseline severity of meniscal extrusion, varus malalignment, and pretreatment degeneration were predictors of poor functional outcomes. Age was not found to be an independent predictor of functional outcome. Conclusion: The current level 3 and 4 evidence suggests that arthroscopic repair may result in slower progression of radiological deterioration compared with meniscectomy and nonoperative management. The current literature does not support the exclusion of patients from MRT repair on the basis of age. Patients undergoing acute MRT treatments (repair, debridement, or nonoperative) can be expected to experience improvement in functional outcomes after >12 months. The strength of conclusions are limited because of the paucity of high-quality studies on this subject. Further studies, preferably randomized sham controlled trials with function-oriented rehabilitation programs, are needed to compare treatment strategies and stratification of care based on the risk of meniscal extrusion. Registration: CRD42018085092 (PROSPERO).

The Updated Role of Ultrasound in the Assessment of Knee Osteoarthritis

Background Osteoarthritis (OA) of the knee is the most common form of knee arthritis and a leading cause of chronic disability. Objective The aim of the current study is to reassess the utility of the updated ultrasound in the patients with knee osteoarthritis and outline its clinical application. Patients and Methods The studied group included 36 patient 23females and 13 males with their ages ranged between 39 and 58 years (average age 44 years). The patients were referred to US examination fulfilling the ACR clinical criteria for knee OA after orthopedic and /or rheumatologist consultation. The study was performed in Radiodiagnosis department Ain Shams University Hospitals (20 patients ) and at one private center (16 patients). Results There was a discrepancy between the results obtained by clinical examination and those demonstrated by ultrasonography. Clinical examination detected 22 (61.1%) of our cases. Prevalence of US findings in our cases were femoral articular degeneration in 28 (77.7%) patients, Tibiofemoral osteophytes were seen in 26 patients (72.2%), knee effusion in 22 patients (61.1%),meniscal extrusion in 22 patients (61.1%) meniscal degeneration in 17 patients (47.2%) and synovial hypertrophy in 15patients (41.6%). Baker’s cysts were demonstrated in 14patients (38.8%) while pes anserine syndrome was demonstrated in 4 cases. Meniscal degeneration and meniscal extrusion were correlated significantly with femoral cartilage degeneration (P&lt;.001). Although knee effusion did not correlate with advanced knee effusion did significantly (P &gt; 0.05). Baker's cysts is statistically related to the presence and severity of mensical changes and also related to the degree of femoral articular cartilage degeneration. Conclusion US is a valuable technique that can assess soft tissue structures within the knee and their involvement in the osteoarthritic process .US enables in guiding and monitoring therapy through detection of knee structural damage.

The Natural History of Medial Meniscal Root Tears: A Biomechanical and Clinical Case Perspective

Posterior medial meniscus root tears (PMMRTs) make up a relatively notable proportion of all meniscus pathology and have been definitively linked to the progression of osteoarthritis (OA). While known risk factors for development of OA in the knee include abnormal tibial coronal alignment, obesity and female gender, PMMRTs have emerged in recent years as another significant driver of degenerative disease. These injuries lead to an increase in average contact pressure in the medial compartment, along with increases in peak contact pressure and a decrease in contact area relative to the intact state. Loss of the root attachment impairs the function of the entire meniscus and leads to meniscal extrusion, thus impairing the force-dissipating role of the meniscus. Anatomic meniscus root repairs with a transtibial pullout technique have been shown biomechanically to restore mean and peak contact pressures in the medial compartment. However, nonanatomic root repairs have been reported to be ineffective at restoring joint pressures back to normal. Meniscal extrusion is often a consequence of nonanatomic repair and is correlated with progression of OA. In this study, the authors will describe the biomechanical basis of the natural history of medial meniscal root tears and will support the biomechanical studies with a case series including patients that either underwent non-operative treatment (5 patients) or non-anatomic repair of their medial meniscal root tears (6 patients). Using measurements derived from axial MRI, the authors will detail the distance from native root attachment center of the non-anatomic tunnels and discuss the ongoing symptoms of those patients. Imaging and OA progression among patients who were treated nonoperatively before presentation to the authors will be discussed as well. The case series thus presented will illustrate the natural history of meniscal root tears, the consequences of non-anatomic repair, and the findings of symptomatic meniscal extrusion associated with a non-anatomic repair position of the meniscus.