Determination of Normal Reference Values for Meniscal Extrusion Using Ultrasonography During the Different Range of Motion

Abstract

Objectives It is essential to know the normal extrusion measures in order to detect pathological ones. In this study, we aimed to define some normal reference values for meniscal extrusion in the normal knees during different ranges of motion. Methods The amount of anterior and posterior portion of meniscal extrusion among 21 asymptomatic volunteers (42 knees) were tracked in 0, 45, and 90° of knee flexion using an ultrasound machine. The repeated measures analysis of variance (ANOVA) was used to show the interaction between the amounts of meniscal extrusion and the different degrees of knee flexion. Results The anterior portion of the lateral menisci at full knee extension (0.59 ± 1.40) and the posterior portion of the medial menisci during 90° flexion (3.06 ± 2.36) showed the smallest and the highest mean amount of extrusion, respectively. The normal average amounts of anterior extrusion were 1.12 ± 1.17 and 0.99 ± 1.34 mm for medial and lateral menisci, respectively. The posterior meniscal normal extrusions were significantly increasing in both medial and lateral menisci during the survey (F = 20.250 and 11.298; both P values <.001) as they were measured 2.37 ± 2.16 and 1.53 ± 2.18 mm in order. Conclusions The medial meniscus can extrude 1.74 ± 1.84 mm normally while this amount was 1.26 ± 1.82 mm for the lateral meniscus. These measures commonly increased with the rising of knee flexion motion. Likewise, the posterior portion showed more extrusion than the anterior portion on both sides. These measures commonly increased with higher knee flexion.

Odontoid fracture complicating ankylosing spondylitis presenting with cervical canal stenosis and quadriparesis: A case report with 5-year follow-up and review of the literature

“…Table 1 shows some of the cases of AS diagnosed with odontoid fractures. As demonstrated in that table, type II odontoid fracture, which was the most common type in the general population [12] , [13] , was more common among the cases with AS relative to other types of odontoid fractures. Also, it is worth mentioning that low-energy traumas, especially falling, were the major cause of odontoid fractures in patients with AS.…”

Extrusion and meniscal mobility evaluation in case of ramp lesion injury: a biomechanical feasibility study by 7T magnetic resonance imaging and digital volume correlation

“…In an ultrasound-based study, Kawaguchi et al (2012) showed that physiologic loading causes mild meniscal extrusion. Another ultrasound study demonstrated that the posterior portion experiences greater extrusion than the anterior portion, particularly as regards the medial meniscus (Sharafat Vaziri et al, 2022). Additionally, research has explored meniscal displacements and 3D morphological changes under knee weight-bearing and early flexion conditions in healthy adults, utilizing MRI (Liu et al, 2021).…”

“…Mechanical loading can significantly deform the menisci in knee extension; however, this effect is limited during knee flexion (Liu et al, 2021). In contrast, anteroposterior mobility commonly increases with the rise of knee flexion motion (Sharafat Vaziri et al, 2022). For this reason, the data concerning lateromedial displacement (X) appear to be more informative.…”

Hypermobile lateral meniscus: A systematic review of current treatment options

“…HLM is usually underdiagnosed due to unspecific symptoms and often a normal physical examination and magnetic resonance imaging (MRI) of the afflicted patients [2,3,38,47]. Unlike routine knee examinations, which reveal no abnormalities, it is reported that placing the patient's knee in the figureof-4 position can reproduce the same symptoms, helping to confirm the HLM diagnosis [3].…”