scholarly journals An Approach to Robotic Testing of the Wrist Using Three-Dimensional Imaging and a Hybrid Testing Methodology

2020 ◽  
Vol 142 (6) ◽  
Author(s):  
Rohit Badida ◽  
Edgar Garcia-Lopez ◽  
Claire Sise ◽  
Douglas C. Moore ◽  
Joseph J. Crisco
Keyword(s):  
Degrees Of Freedom ◽  
Soft Tissues ◽  
Wrist Joint ◽  
Ct Imaging ◽  
Coordinate Systems ◽  
Standard Material ◽  
Wrist Motion ◽  
Flexion Extension ◽  
Robotic Testing

Abstract Robotic technology is increasingly used for sophisticated in vitro testing designed to understand the subtleties of joint biomechanics. Typically, the joint coordinate systems in these studies are established via palpation and digitization of anatomic landmarks. We are interested in wrist mechanics in which overlying soft tissues and indistinct bony features can introduce considerable variation in landmark localization, leading to descriptions of kinematics and kinetics that may not appropriately align with the bony anatomy. In the wrist, testing is often performed using either load or displacement control with standard material testers. However, these control modes either do not consider all six degrees-of-freedom (DOF) or reflect the nonlinear mechanical properties of the wrist joint. The development of an appropriate protocol to investigate complexities of wrist mechanics would potentially advance our understanding of normal, pathological, and artificial wrist function. In this study, we report a novel methodology for using CT imaging to generate anatomically aligned coordinate systems and a new methodology for robotic testing of wrist. The methodology is demonstrated with the testing of 9 intact cadaver specimens in 24 unique directions of wrist motion to a resultant torque of 2.0 N·m. The mean orientation of the major principal axis of range of motion (ROM) envelope was oriented 12.1 ± 2.7 deg toward ulnar flexion, which was significantly different (p < 0.001) from the anatomical flexion/extension axis. The largest wrist ROM was 98 ± 9.3 deg in the direction of ulnar flexion, 15 deg ulnar from pure flexion, consistent with previous studies [1,2]. Interestingly, the radial and ulnar components of the resultant torque were the most dominant across all directions of wrist motion. The results of this study showed that we can efficiently register anatomical coordinate systems from CT imaging space to robotic test space adaptable to any cadaveric joint experiments and demonstrated a combined load-position strategy for robotic testing of wrist.

Finite Element Model of the Human Knee Joint to Study Tibio-Femoral Contact Mechanics

2000 ◽  
Author(s):  
Tammy Haut Donahue ◽  
Maury L. Hull ◽  
Mark M. Rashid ◽  
Christopher R. Jacobs
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Degrees Of Freedom ◽  
Soft Tissues ◽  
Element Model ◽  
Human Knee ◽  
Human Knee Joint ◽  
Solid Models ◽  
Flexion Extension ◽  
A New Technique

Abstract A finite element model of the tibio-femoral joint in the human knee was created using a new technique for developing accurate solid models of soft tissues (i.e. cartilage and menisci). The model was used to demonstrate that constraining rotational degrees of freedom other than flexion/extension when the joint is loaded in compression markedly affects the load distribution between the medial and lateral sides of the joint. The model also was used to validate the assumption that the bones can be treated as rigid.

Multibody Analysis and Control of a Full-Wrist Exoskeleton for Tremor Alleviation

2020 ◽  
Vol 142 (12) ◽  
Author(s):  
Jiamin Wang ◽  
Oumar R. Barry
Keyword(s):  
Degrees Of Freedom ◽  
Controller Design ◽  
Wrist Joint ◽  
Three Dimensional ◽  
Design Parameters ◽  
Light Power ◽  
Multibody Modeling ◽  
Flexion Extension ◽  
Reliable Performance ◽  
Rotational Joint

Abstract Uncontrollable shaking in the human wrist, caused by pathological tremor, can significantly undermine the power and accuracy in object manipulation. In this paper, the design of a tremor alleviating wrist exoskeleton (TAWE) is introduced. Unlike the works in the literature that only consider the flexion/extension (FE) motion, in this paper, we model the wrist joint as a constrained three-dimensional (3D) rotational joint accounting for the coupled FE and radial/ulnar deviation (RUD) motions. Hence TAWE, which features a six degrees-of-freedom (DOF) rigid linkage structure, aims to accurately monitor, suppress tremors, and provide light-power augmentation in both FE and RUD wrist motions. The presented study focuses on providing a fundamental understanding of the feasibility of TAWE through theoretical analyses. The analytical multibody modeling of the forearm–TAWE assembly provides insight into the necessary conditions for control, which indicates that reliable control conditions in the desired workspace can be acquired by tuning the design parameters. Nonlinear regressions are then implemented to identify the information that is crucial to the controller design from the unknown wrist kinematics. The proposed analytical model is validated numerically with V-REP and the result shows good agreement. Simulations also demonstrate the reliable performance of TAWE under controllers designed for tremor suppression and movement assistance.

scholarly journals Design of Shape Memory Alloy-Based Soft Wearable Robot for Assisting Wrist Motion

2019 ◽  
Vol 9 (19) ◽  
pp. 4025 ◽  
Author(s):  
Jaeyeon Jeong ◽  
Ibrahim Bin Yasir ◽  
Jungwoo Han ◽  
Cheol Hoon Park ◽  
Soo-Kyung Bok ◽  
...  
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Degrees Of Freedom ◽  
Wrist Flexion ◽  
Wearable Robot ◽  
Maximum Torque ◽  
Wrist Motion ◽  
Contraction Ratio ◽  
Flexion Extension ◽  
The Average Range

In this paper, we propose a shape memory alloy (SMA)-based wearable robot that assists the wrist motion for patients who have difficulties in manipulating the lower arm. Since SMA shows high contraction strain when it is designed as a form of coil spring shape, the proposed muscle-like actuator was designed after optimizing the spring parameters. The fabricated actuator shows a maximum force of 10 N and a maximum contraction ratio of 40%. The SMA-based wearable robot, named soft wrist assist (SWA), assists 2 degrees of freedom (DOF) wrist motions. In addition, the robot is totally flexible and weighs 151g for the wearable parts. A maximum torque of 1.32 Nm was measured for wrist flexion, and a torque of larger than 0.5 Nm was measured for the other motions. The robot showed the average range of motion (ROM) with 33.8, 30.4, 15.4, and 21.4 degrees for flexion, extension, ulnar, and radial deviation, respectively. Thanks to the soft feature of the SWA, time cost for wearing the device is shorter than 2 min as was also the case for patients when putting it on by themselves. From the experimental results, the SWA is expected to support wrist motion for diverse activities of daily living (ADL) routinely for patients.

Foot Movement and Tendon Excursion: An In Vitro Study

1994 ◽  
Vol 15 (7) ◽  
pp. 386-395 ◽  
Author(s):  
Beat Hintermann ◽  
Benno M. Nigg ◽  
Christian Sommer
Keyword(s):  
Degrees Of Freedom ◽  
Function Analysis ◽  
In Vitro Study ◽  
Tibialis Posterior ◽  
Flexor Hallucis Longus ◽  
Moment Arms ◽  
In Vitro Investigation ◽  
Flexion Extension ◽  
Tendon Excursion

The purpose of this study was to determine tendon excursions resulting from selected foot movement and to derive moment arms with respect to the eversion-inversion and flexion-extension axes of the foot. A lower legholding device with 6 degrees of freedom was used for the in vitro investigation of 15 fresh foot-leg specimens. Although high variation among the subjects existed, there was a pronounced uniformity of tendon excursion throughout a given foot eversion-inversion or flexion-extension range of motion. With reference to the tibialis posterior (1.00), average inverter moment arms with respect to the foot eversion-inversion axis were found to be as follows: flexor digitorum longus, 0.75; flexor hallucis longus, 0.62; tibialis anterior, 0.59; soleus, 0.24; extensor hallucis longus, 0.22; extensor digitorum longus, −0.26; peroneus longus, −0.82; and peroneus brevis, −0.85. A trend toward decreasing evertor/invertor moment arms was observed during the ranges of foot eversion, as well as when the foot was in flexion. Flexor and extensor moment arms were found to be substantially dependent on foot flexion-extension angle. Increasing flexor moment arms were observed when rotating the foot throughout the range from extension to flexion. The obtained results may have significant implications in foot surgery, muscle function analysis, and general considerations of foot function.

scholarly journals Biomechanical Stability of Primary and Revision Sacroiliac Joint Fusion Devices: A Cadaveric Study

2020 ◽  
pp. 219256822094802
Author(s):  
Jake Carbone ◽  
Isaac Swink ◽  
Thomas Muzzonigro ◽  
Daniel Diehl ◽  
Michael Oh ◽  
...  
Keyword(s):  
Axial Compression ◽  
Sacroiliac Joint ◽  
Degrees Of Freedom ◽  
Bone Ingrowth ◽  
Translational Motion ◽  
Pubic Symphysis ◽  
Primary Treatment ◽  
Titanium Implants ◽  
Flexion Extension

Study Design: An in vitro biomechanics study. Objective: To evaluate the efficacy of triangular titanium implants in providing mechanical stabilization to a sacroiliac joint with primary and revision sized implants. Methods: Ten lumbopelvic cadaveric specimens were tested in 4 stages: intact, pubic symphysis sectioned, primary, and simulated revision. Primary treatment was performed using 3 laterally placed triangular titanium implants. To simulate revision conditions before and after bone ingrowth and ongrowth on the implants, 7.5-mm and 10.75-mm implants were randomly assigned to one side of each specimen during the simulated revision stage. A 6 degrees of freedom spinal loading frame was used to load specimens in 4 directions: flexion extension, lateral bending, axial torsion, and axial compression. Biomechanical evaluation was based on measures of sacroiliac joint rotational and translational motion. Results: Both primary and revision implants showed the ability to reduce translational motion to a level significantly lower than the intact condition when loaded in axial compression. Simulated revision conditions showed no statistically significant differences compared with the primary implant condition, with the exception of flexion-extension range of motion where motions associated with the revised condition were significantly lower. Comparison of rotational and translation motions associated with the 7.5- and 10.75-mm implants showed no significant differences between the treatment conditions. Conclusions: These results indicate that implantation of laterally placed triangular titanium implants significantly reduces the motion of a sacroiliac joint using either the primary and revision sized implants. No statistically significant differences were detected when comparing the efficacy of primary, 7.5-mm revision, or 10.75-mm revision implants.

Analysis of wrist bone motion before and after SL-ligament resection

2016 ◽  
Vol 61 (3) ◽  
pp. 345-357 ◽  
Author(s):  
Jörg Eschweiler ◽  
Jan Philipp Stromps ◽  
Björn Rath ◽  
Norbert Pallua ◽  
Klaus Radermacher
Keyword(s):  
Degrees Of Freedom ◽  
Wrist Joint ◽  
Tracking System ◽  
Longitudinal Axis ◽  
Ligament Injury ◽  
Scaphoid Bone ◽  
Electromagnetic Tracking ◽  
Ulnar Deviation ◽  
Flexion And Extension

Abstract The analysis of the three-dimensional motion of wrist joint components in the physiological and injured wrist is of high clinical interest. Therefore, the purpose of this in vitro study was to compare the motion of scaphoid, lunate and triquetrum during physiological wrist motion in flexion and extension, and in radial- and ulnar-deviation, with those motion patterns after complete resection of the scapho-lunate-ligament. Eight fresh frozen cadaver wrists were carefully thawed and prepared for the investigation with an electromagnetic tracking system by implantation of measurement coils with 6 degrees of freedom. Electromagnetic tracking enabled the motion analysis of the scaphoid, lunate, and triquetrum bones with respect to the fixed radius in three planes of passive motion. After scapho-lunate-ligament injury changes in the translational and rotational motion pattern especially of the scaphoid bone occurred in dorsal-volar directions during flexion and extension, radial- and ulnar-deviation, and during rotation around the radio-ulnar- and longitudinal-axis of the wrist.

3D kinematics of the interphalangeal joints in the forelimb of walking and trotting horses

2007 ◽  
Vol 20 (01) ◽  
pp. 01-07 ◽  
Author(s):  
D. H. Sha ◽  
J. A. Stick ◽  
P. Robinson ◽  
H. M. Clayton
Keyword(s):  
Significant Contribution ◽  
Soft Tissues ◽  
External Rotation ◽  
Imaging Techniques ◽  
Proximal Phalanx ◽  
Middle Phalanx ◽  
Coordinate Systems ◽  
Flexion Extension ◽  
Pip Joint ◽  
The Right

SummaryThe objective was to measure 3D rotations of the distal (DIP) and proximal (PIP) interphalangeal joints at walk and trot. 3D trajectories of markers fixed to the proximal phalanx, middle phalanx and the hoof wall of the right forelimb of four sound horses were recorded at 120 Hz. Joint kinematics were calculated in terms of anatomically-based joint coordinate systems between the bone segments. Ranges of motion were similar at walk and trot. Values for the DIP joint were: flexion/extension: 46 ± 3° at walk, 47 ± 4° at trot; internal/ external rotation: 5 ± 1° at walk, 6 ± 3° at trot; and adduction/abduction: 5 ± 2° at walk, 5 ± 3° at trot. Within each gait, kinematic profiles at the DIP joint were similar between horses with the exception of adduction/abduction during breakover, which may vary depending on the direction of hoof rotation over the toe. Knowledge of the types and amounts of motion at the DIP joint will be useful in understanding the aetiology and treatment of injuries to the soft tissues, which are being recognized more frequently through the use of sensitive imaging techniques. Ranges of motion for the PIP joint were: flexion/extension: 13 ± 4° at walk, 14 ± 4° at trot; adduction/abduction: 3 ± 1° at walk, 3 ± 1° at trot; and internal/external rotation: 3 ± 1° at walk, 4 ± 1° at trot. The PIP joint made a significant contribution to flexion/extension of the digit. During surgical arthrodesis, the angle of fusion may be important since loss of PIP joint extension in late stance is likely to be accommodated by increased extension of the DIP joint.

Effect of scaphoid and triquetrum excision after limited stabilisation on cadaver wrist movement

2009 ◽  
Vol 34 (5) ◽  
pp. 614-617 ◽  
Author(s):  
G. I. BAIN ◽  
A. SOOD ◽  
N. ASHWOOD ◽  
P. C. TURNER ◽  
Q. A. FOGG
Keyword(s):  
Range Of Motion ◽  
Wrist Joint ◽  
Wrist Movement ◽  
Wrist Motion ◽  
Flexion Extension ◽  
Before And After

This study assessed the effect of excision of the scaphoid and triquetrum on the range of motion of the embalmed cadaver wrist joint after midcarpal stabilisation. The range of motion was measured in 12 cadaver wrists before and after stabilisation of the joints between the lunate, capitate, triquetrum and hamate. This was measured again following resection of the scaphoid and then the triquetrum. Scaphoid excision after four-corner stabilisation increased the radioulnar (RU) arc by 12° and the flexion–extension (F–E) arc by 10°. Subsequent excision of the triquetrum, to produce a three-corner stabilisation, further increased the RU arc by 7° and the F–E arc by 6°. Three-corner stabilisation with excision of scaphoid and triquetrum improved wrist motion in embalmed cadavers.

Biological and biomedical applications of collagenous biomaterials

1990 ◽  
Vol 48 (3) ◽  
pp. 856-857
Author(s):  
Yasushi P. Kato ◽  
Michael G. Dunn ◽  
Frederick H. Silver ◽  
Arthur J. Wasserman
Keyword(s):  
Biomedical Applications ◽  
Soft Tissues ◽  
Collagen Fibers ◽  
Bone Collagen ◽  
Cover Slip ◽  
Fibroblast Migration ◽  
Cellular Expression ◽  
Defect Repair

Collagenous biomaterials have been used for growing cells in vitro as well as for augmentation and replacement of hard and soft tissues. The substratum used for culturing cells is implicated in the modulation of phenotypic cellular expression, cellular orientation and adhesion. Collagen may have a strong influence on these cellular parameters when used as a substrate in vitro. Clinically, collagen has many applications to wound healing including, skin and bone substitution, tendon, ligament, and nerve replacement. In this report we demonstrate two uses of collagen. First as a fiber to support fibroblast growth in vitro, and second as a demineralized bone/collagen sponge for radial bone defect repair in vivo.For the in vitro study, collagen fibers were prepared as described previously. Primary rat tendon fibroblasts (1° RTF) were isolated and cultured for 5 days on 1 X 15 mm sterile cover slips. Six to seven collagen fibers, were glued parallel to each other onto a circular cover slip (D=18mm) and the 1 X 15mm cover slip populated with 1° RTF was placed at the center perpendicular to the collagen fibers. Fibroblast migration from the 1 x 15mm cover slip onto and along the collagen fibers was measured daily using a phase contrast microscope (Olympus CK-2) with a calibrated eyepiece. Migratory rates for fibroblasts were determined from 36 fibers over 4 days.

3D Culture Modelling: An Emerging Approach for Translational Cancer Research in Sarcomas

2020 ◽  
Vol 27 (29) ◽  
pp. 4778-4788 ◽  
Author(s):  
Victoria Heredia-Soto ◽  
Andrés Redondo ◽  
José Juan Pozo Kreilinger ◽  
Virginia Martínez-Marín ◽  
Alberto Berjón ◽  
...  
Keyword(s):  
High Throughput Screening ◽  
Cancer Biology ◽  
Soft Tissues ◽  
Three Dimensional ◽  
3D Culture ◽  
Resistance Mechanisms ◽  
In Vitro Models ◽  
Tumour Spheroids ◽  
Current Therapies

Sarcomas are tumours of mesenchymal origin, which can arise in bone or soft tissues. They are rare but frequently quite aggressive and with a poor outcome. New approaches are needed to characterise these tumours and their resistance mechanisms to current therapies, responsible for tumour recurrence and treatment failure. This review is focused on the potential of three-dimensional (3D) in vitro models, including multicellular tumour spheroids (MCTS) and organoids, and the latest data about their utility for the study on important properties for tumour development. The use of spheroids as a particularly valuable alternative for compound high throughput screening (HTS) in different areas of cancer biology is also discussed, which enables the identification of new therapeutic opportunities in commonly resistant tumours.

Sign in / Sign up

Export Citation Format

Share Document