Differentiation of strains in the lateral and medial bands of the iliofemoral ligament: A segmental approach

Iliofemoral ligament strains have been assessed in a circumscribed portion, limiting the information regarding the strains in the proximal, mid and distal portions. The purpose of this study is to describe the longitudinal and transversal strain within the proximal, mid and distal portions of the lateral and medial bands of the iliofemoral ligament. Ten fresh cadaveric specimens were assessed. The iliofemoral ligaments were divided into medial and lateral bands. Hemispherical beads (2.6 mm) were placed on the lateral and medial borders of each band. Four positions were assessed: abduction, extension, internal and external rotations combined with extension. The hemispherical beads were scanned at the end range of motion using a laser scanner. The three-dimensional position of each bead was used to estimate longitudinal and transversal strains. A three-factor ANOVA was used to compare movements, borders, and portions within each ligament for longitudinal strains. A one-way ANOVA was used to compare transversal strains between portions. This technique showed mean reliability (ICC: 2, 1) of 0.90 ± 0.06. The external rotation showed the highest strains in both ligaments (p < 0.05). Abduction showed a significant difference between the lateral and medial borders in both bands (p = 0.001). Eight movement-border combinations showed a significant difference between proximal, medial, and lateral portions (p < 0.005). According to our results, there is a clear effect of portions (proximal, mid and distal) within the ligament and movements. Abduction shows the lowest strains longitudinally but the largest strains transversally. Although we do not know the impact of this phenomenon, future studies should assess the strains following hip arthroscopies. The latter might improve the impact of this procedure on hip biomechanics. Lastly, the iliofemoral ligament should be assessed using a segmental approach rather than as a complete unit

Application of ultrasound in spine kinematic determination: A systemic review

Abstract Spine kinematic determination is required to diagnose or rehabilitate back pain due to spinal instability. Ultrasound imaging, as a less harmful and cost‑effective method, has been recently applied to kinematic analysis. This study reviews all available published articles to see how much progress has been made in spine kinematic measurement by ultrasound. In this regard, we searched PubMed, Scopus, and Google Scholar among all available studies until 2021, using keywords such as ultrasound, spine, kinematics, rotation, twist, flexion, and bending. Finally, after identifying and scanning 183 articles, only nine articles were included, which analyzed spine kinematics by ultrasound. Among these nine articles, three reported axial displacements, three reported flexion/extension, and three reported axial rotation. Although ultrasound is a suitable alternative to other kinematic measurement methods, very little research and progress have been made in this area. Today, this method is still not used practically for spine kinematic measurement because the bone scans via ultrasound imaging are challenging to understand, and no three‑dimensional kinematic measurement technique has been reported. However, recent advances in converting ultrasound images into three‑dimensional images can pave the way for further improvements

A new link lifetime estimation method for greedy and contention-based routing in mobile ad hoc networks

Greedy and contention-based forwarding schemes were proposed for mobile ad hoc networks (MANETs) to perform data routing hop-by-hop, without prior discovery of the end-to-end route to the destination. Accordingly, the neighboring node that satisfies specific criteria is selected as the next forwarder of the packet. Both schemes require the nodes participating in the selection process to be within the area that confronts the location of the destination. Therefore, the lifetime of links for such schemes is not only dependent on the transmission range, but also on the location parameters (position, speed and direction) of the sending node and the neighboring node as well as the destination. In this paper, we propose a new link lifetime prediction method for greedy and contention-based routing which can also be utilized as a new stability metric. The evaluation of the proposed method is conducted by the use of stability-based greedy routing algorithm, which selects the next hop node having the highest link stability