Category Ranking
98%
Total Visits
921
Avg Visit Duration
2 minutes
Citations
20
Article Abstract
Understanding the transformation of tendon forces into joint torques would greatly aid in the investigation of the complex temporal and spatial coordination of multiple muscles in finger movements. In this study, the effects of the finger posture on the tendon force transmission within the finger extensor apparatus were investigated. In five cadaver specimens, a constant force was applied sequentially to the two extrinsic extensor tendons in the index finger, extensor digitorum communis and extensor indicis proprius. The responses to this loading, i.e., fingertip force/moment and regional strains of the extensor apparatus, were measured and analyzed to estimate the tendon force transmission into the terminal and central slips of the extensor hood. Repeated measures analysis of variance revealed that the amount of tendon force transmitted to each tendon slip was significantly affected by finger posture, specifically by the interphalangeal (IP) joint angles (p<0.01). Tendon force transmitted to each of the tendon slips was found to decrease with the IP flexion. The main effect of the metacarpophalangeal (MCP) joint angle was not as consistent as the IP angle, but there was a strong interaction effect for which MCP flexion led to large decreases in the slip forces (>30%) when the IP joints were extended. The ratio of terminal slip force:central slip force remained relatively constant across postures at approximately 1.7:1. Force dissipation into surrounding structures was found to be largely responsible for the observed force-posture relationship. Due to the significance of posture in the force transmission to the tendon slips, the impact of finger posture should be carefully considered when studying finger motor control or examining injury mechanisms in the extensor apparatus.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2711535 | PMC |
| http://dx.doi.org/10.1115/1.2978983 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Target recognition and grasping strategies for soft robotic manipulators in unstructured environments.
Rev Sci Instrum
September 2025
Hefei University of Technology, School of Mechanical Engineering, Hefei 230009, China.
In unstructured environments, robots face challenges in efficiently and accurately grasping irregular, fragile objects. To address this, this paper introduces a soft robotic hand tailored for such settings and enhances You Only Look Once v5s (YOLOv5s), a lightweight detection algorithm, to achieve efficient grasping. A rapid pneumatic network-based soft finger structure, broadly applicable to various irregularly placed objects, is designed, with a mathematical model linking the bending angle of the fingers to input gas pressure, validated through simulations.
View Article and Find Full Text PDFComputational model to reproduce fingertip trajectories and arm postures during human three-joint arm movements: minimum muscle-stress-change model.
Biol Cybern
August 2025
Department of Human and Artificial Intelligent Systems, Graduate School of Engineering, University of Fukui, 3-9-1, Bunkyo, Fukui-shi, Fukui, 910-8507, Japan.
Previous studies on the computational principle for solving the movement selection problem for the human arm have primarily focused on hand trajectories associated with the two-joint movements of the shoulder and elbow joints. Further, only a few computational models, that consider the musculoskeletal system, have been investigated. From this perspective, a minimum muscle-stress-change model was evaluated for the fingertip trajectories and arm postures during three-joint movements in the horizontal plane, including wrist joint rotation.
View Article and Find Full Text PDFObject-directed action representations are componentially built in parietal cortex.
Proc Natl Acad Sci U S A
August 2025
Department of Psychology, Carnegie Mellon University, Pittsburgh, PA 15213.
The inferior parietal lobule supports action representations that are necessary to grasp and use objects in a functionally appropriate manner [S. H. Johnson-Frey, , 71-78 (2004)].
View Article and Find Full Text PDFMultiple, not single, recipient muscle tendon transfers produce well-directed thumb-tip forces in lateral pinch grasp: A simulation study with application to restoration of improved grasp after tetraplegia.
J Biomech
October 2025
Swarthmore College, Department of Engineering, 500 College Ave, Swarthmore, PA 19081, United States. Electronic address:
Thumb tendon transfer surgical procedures in patients with cervical spinal injury engage the paralyzed flexor pollicis longus (FPL) muscle to enable lateral pinch grasp. However, functional outcomes are mixed, in part because the FPL cannot consistently produce force at the thumb-tip to promote a stable grasp. We used simulation to investigate whether a multiple recipient muscle tendon transfer, targeting sets of paralyzed muscles driven by a single donor muscle, could outperform a single recipient muscle tendon transfer with the FPL alone and restore lateral pinch.
View Article and Find Full Text PDFMagnitude and Location of Isolated Thumb Forces in Control and LRTI Surgery Participants: Mapping Force to Three-Dimensional Kinematics.
J Biomech Eng
November 2025
Mechanical Engineering Department, 428 South Shaw Lane, 2555, East Lansing, MI 48824.
The thumb carpometacarpal (CMC) joint is highly susceptible to osteoarthritis (OA), often leading to weakness. As the most functionally important finger, it is vital to monitor thumb force, both the magnitude and location, to track disease progression and evaluate treatments and surgeries for CMC OA. However, current tools fail to measure isolated thumb force or capture varied thumb postures.
View Article and Find Full Text PDF