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

Abstract

PurposeMedial 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. MethodsThe 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. ResultsTen 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]. ConclusionRadiographic 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 evidenceIV.

Subchondral bone remodeling patterns in larger animal models of meniscal injuries inducing knee osteoarthritis – a systematic review

“…In the knee, both menisci complement and protect the osteochondral unit [ 25 ]. Meniscus injury is common [ 20 , 32 ], and meniscus tissue insufficiency and loss are one of the most important causes of knee OA [ 5 – 7 , 21 , 49 , 52 ]. The principle of inducing a defined meniscal lesion is applied in many animal models to model OA initiation and development [ 42 , 50 ].…”

Favorable early outcomes of medial unicompartimental knee arthroplasty in active patients presenting a degenerative medial meniscus root tear with meniscal extrusion and mild radiographic osteoarthritis

“…Biomechanical studies have demonstrated that the medial meniscus transmits 50% of the joint load in the medial compartment and that at least 50% of the compressive load of the knee joint is transmitted through the meniscus in extension [1,2]. As a consequence of a MME, the reduced tibiofemoral contact area increases mean and peak weight-bearing forces resulting in a diverged knee kinematic and ultimately leading to an increased risk of osteophytosis, chondral lesions, loss of cartilage, and eventually osteoarthritis (OA) [3][4][5][6][7][8][9].…”

“…MME frequently occurs in conjunction with radial medial meniscus tears (MMT), with an incidence of 46.7%, particularly in medial meniscus root tears (MMRT), up to 83.3% of cases [4].…”

Insufficient restoration of meniscal extrusion by transtibial pullout repair for medial meniscus posterior root tears

“…A medial meniscus posterior root tear (MMPRT) is an injury to the posterior meniscal attachment of the tibia that causes abnormal knee joint kinematics. MMPRTs disrupt the hoop function and cause medial meniscus extrusion (MME) [9,25,31,34]. Conservative treatment of MMPRTs is not always efective, and meniscal repair is more efective than both partial meniscectomy and conservative treatment [4,21,22,24].…”