Correlation Between Medial Meniscal Extrusion Determined by Dynamic Ultrasound and Magnetic Resonance Imaging Findings of Medial‐Type Knee Osteoarthritis in Patients With Knee Pain

Abstract

Objectives-The aim of our study was to investigate the relationship between medial meniscal extrusion (MME) determined by dynamic ultrasound (US) and magnetic resonance imaging findings of medial-type knee osteoarthritis (OA).Methods-Single knees of 102 patients with knee pain were assessed by radiography, dynamic US, and magnetic resonance imaging. All knee radiographs were interpreted and grouped according to the Kellgren-Lawrence (KL) scale. Medial meniscal extrusion in non-weight-bearing and weight-bearing positions and the difference of these values (ΔMME) were measured by dynamic US. The medial tibiofemoral compartments of all knees were evaluated and grouped according to the Whole-Organ Magnetic Resonance Imaging Score (WORMS). Mean values of non-weight-bearing MME, weight-bearing MME, and ΔMME AE standard deviations for groups formed according to the KL scale and WORMS system were compared.Results-We demonstrated that different from non-weight-bearing MME, weight-bearing MME was significantly correlated with not only high grades but also lower grades of cartilage damage and subchondral bone marrow lesions in medial-type knee OA. Although the difference in non-weight-bearing MME between cartilage status groups 1 and 2 was not significant (P = .071), there were significant differences in of weight-bearing MME between groups 1 and 2, between groups 2 and 3, and between groups 3 and group 4 (P = .003, .002, and .032, respectively).Conclusions-We found statistically significant associations between MME values and the severity of the OA findings according to both the KL scale and WORMS system. We offer dynamic US as an initial tool for the diagnosis and a screening method to estimate the severity of knee OA.

Sonographic evaluation of lateral meniscal extrusion: implementation and validation

“…This indicates that a combined anterior cruciate ligament reconstruction and lateral meniscal radial tear repair is not able to restore lateral ME to the level of the healthy contralateral knee. Thus, ME is an indicator for various pathologies [7,8,12] and can be used as a screening tool for knee joint osteoarthritis [10,11,29]. Additionally, recent studies [30,31] have demonstrated that ME represents a negative prognostic factor regarding the outcome of arthroscopic partial meniscectomy.…”

“…Numerous studies [2,3,9,10,13,17,29] have investigated medial ME using US. To obtain reliable measurements, distinct landmarks were defined, including the medial femoral epicondyle, the medial tibial condyle and the threelayered medial collateral ligament.…”

“…Therefore, reliability was only confirmed for knees free of joint degeneration. Osteoarthritis is accompanied by synovial hypertrophy [39], osteophytes and increased ME [2,5,[9][10][11], potentially hindering reliable US assessment. However, no MRI examination was performed in the healthy volunteers assigned to Group I.…”

“…The amount of extrusion is influenced by several patient-and joint-related parameters. Increasing age or body mass index (BMI) [3,8] as well as the presence of osteoarthritis [2,5,[9][10][11] or meniscal tears [7,8,12] lead to higher levels of ME. In addition, prolonged periods of meniscus stress may cause a reversible increase in extrusion [13].…”

“…In clinical practice, ME an indicator of various pathologies needs to be recorded quickly, simply and cost-effectively. One technique meeting these requirements is ultrasound (US), which allows for dynamic assessments and has been successfully used for measurements of medial ME in numerous studies [3,10,[16][17][18][19].…”