Meniscal movement

Abstract

W e present the first study in vivo of meniscal movement in normal knees under load. Using an open MR scanner, allowing imaging in physiological positions in near to real-time, 16 young footballers were scanned moving from full extension to 90°fl exion in the sagittal and coronal planes. Excursion of the meniscal horns, radial displacement and meniscal height were measured. On weight-bearing, the anterior horn of the medial meniscus moves through a mean of 7.1 mm and the posterior horn through 3.9 mm, with 3.6 mm of mediolateral radial displacement. The height of the anterior horn increases by 2.6 mm and that of the posterior horn by 2.0 mm. The anterior horn of the lateral meniscus moves 9.5 mm and the posterior horn 5.6 mm, with 3.7 mm of radial displacement. The height of the anterior horn increases by 4.0 mm, and that of the posterior horn by 2.4 mm. In non-weight-bearing, the anterior horn of the medial meniscus moves 5.4 mm and the posterior horn 3.8 mm, with 3.3 mm of radial displacement. The anterior horn of the lateral meniscus moves 6.3 mm, and the posterior horn 4.0 mm, with 3.4 mm of radial displacement. The most significant differences between weight-bearing and non-weight-bearing were the movement and vertical height of the anterior horn of the lateral meniscus.

Validation of a method for combining biplanar radiography and magnetic resonance imaging to estimate knee cartilage contact

“…Note that this is a limitation of only the laser scan methodology; the biplane imaging method described can be (and has been) used for assessing tibiofemoral cartilage contact during a variety of dynamic, functional activities. MRI enables direct measurement of meniscal position and function as well as cartilage contact, but only under slow-moving or static, simulated loading conditions [11, 70]). Both the imaging speed and the space constraints of the MRI magnet proscribe use of MRI for joint function assessment during dynamic, functional tasks such as normal-speed walking or running.…”

“…Articular cartilage contact has been assessed in the knee [1–9]. Methods for analyzing knee contact have typically utilized magnetic resonance imaging (MRI) to directly assess opposing cartilage and meniscal tissues in both unloaded supine conditions and simulated loading during low load static and dynamic flexion activities [2, 8, 10, 11]. The low temporal sampling rates and physically restrictive environment of the MRI magnet, however, limit testing to loading magnitudes and ambulatory speeds that are far below those typically encountered during activities of daily living.…”

A three-dimensional finite element analysis of the combined behavior of ligaments and menisci in the healthy human knee joint

“…Menisci are a complex biomechanical system in themselves, with a fundamental role in load transmission, shock absorption, proprioception, improvement of stability and lubrication (Vedi et al, 1999). Load distribution over an incongruent joint surface is effectively redistributed by the menisci by maintaining maximal congruency (Walker and Erkman, 1975).…”

MR imaging of the forefoot under weight‐bearing conditions: Position‐related changes of the neurovascular bundles and the metatarsal heads in asymptomatic volunteers

“…Newer magnet designs, originally developed for interventional MR imaging, allow multiplanar imaging in weight-bearing positions (16,17,25,26). MR imaging in the weight-bearing position is of special interest in MR imaging of the forefoot, since MR imaging is unique in providing information about soft tissues and their relation to bony structures.…”