Towards a New Generation of Prostheses : From Research to Retail

"An inaugural lecture delivered on 3 May 2016"

THE CONTRIBUTION OF UPPER LIMB JOINTS IN THE DEVELOPMENT OF RACKET VELOCITY IN THE BADMINTON SMASH

The contributions of the upper limb joints in developing the racket-head velocity were calculated using the 3D video analysis technique. The performance of 13 male players in the single and double competitions during the Thomas/Uber Cup 2000 was recorded. The major contributor to the mean racket-head's linear velocity of 34.6 ms·1 at impact was the wrist (26.5 %). The statistical analysis carried out showed that the dynamics of wrist served to increase the speed of the racket at impact. However, the study showed no significant correlation between the racket speed at impact and the velocity· of the shuttlecock after impact. A relationship between racket speed and post-impact acceleration of shuttlecock did exist

JOINT ANGLE PRODUCTION DURING SQUASH FOREHAND AND BACKHAND STROKE

The paper discusses the production of joint angles at the upper limb joint of forehand and backhand strokes during contact phase. There are eight significant joint anatomical profiles that were investigated namely; trunk flexion, trunk lateral flexion, trunk rotation, shoulder adduction, shoulder rotation, elbow flexion, wrist flexion and wrist pronation.. A female intermediate squash player participated in this study and data were collected using a 250 Hz VICON MX motion analysis system. The results show that the extension of the elbow joint and pronation/supination of the wrist played important role in generating racquet head velocity during contact

Determining Foot-Ankle Mechanism Design by Mapping the Relationships Among Bones, Joints, and Ground Reaction Force

This work investigates the following questions—why the bones and the joints are arranged in that way, why it is different from other primates, and how could it be imitated to develop a foot-ankle mechanism. Mathematical models were developed and were based on the relationship among the anatomy of bones and joints, the normalized ground reaction forces that acted on certain nodes on the footprint. Using the model, a custom design prosthetic foot was assembled. It was tested on a robot arm that simulated a walking gait. The stance phase cycle performed on the prototype, and the commercial feet were completed within approximately 1.08 seconds and 1.38 seconds, respectively. The techniques used, however, may require further studies because the prototype foot was not tested on patients. At this stage, the techniques are sufficient to justify that the prototype foot design should consist of an ankle-foot mechanism and a flexible keel. Therefore, proper mappings of bones and joints; and modeling of foot biomechanics is found useful in design and development of prosthetic feet activities

An approach for the correlation of EMG signals and the rectification of PTB sockets

Prosthesis is often used to restore the appearance and functional mobility to individuals following limb amputatio n. The purpose of this study is to investigate the correlation between the electromyogram (EMG) signals with the rectication of patellar tendon bearing (PTB) socket. Six PTB sockets are manufactured with di erent compression depths at the patellar tendon region. Experiments for the subject are carried out to obtain the EMG signals using EMG telemetry system. From this study, it is found that there exists some kinds of pattern as the depths of PTB rectication is changed. As the PTB rectication depth is increased, the EMG activity rises generally yet in an N pattern for the quadriceps group for both left and right legs of the amputee. The results of this case study will lead to an appropriate range of rectication depths for prosthetists in the manufacturing of PTB sockets, and perhaps the identication of the most suitable depth for optimum transtibial amputee ambulation

THREE-DIMENSIONAL CINEMATOGRAPHIC ANALYSIS: ENLARGING A CALIBRATED VOLUME

Doing research in open games requires a calibrating system as large as the size of the playing court. In this paper a new reference structure, poles system, which could encompass the size of a playing court, is developed. Comparisons between the currently available frame and the poles systems are made. The results showed that the poles are comparable to those obtained using the Peak calibration frame, despite the difference in the dimensions of the structures, the location of the control points, as well as the physical characteristics of the structures

A COMPARATIVE STUDY ON KINEMATICS PARAMETERS BETWEEN THE SEPAK KUDA SERVE AND THE SEPAK SILA SERVE IN SEPAK TAKRAW

The most important and effective skill in a sepak takraw game is the serve. In 1995, during the 18th SEA Games, a new technique of serving, 'sepak kuda' was introduced. The sepak kuda serve is well known as the most powerful serve compared to the more traditional serve of 'sepak sila'. The purpose of this study was to make a comparative study on kinematics parameters in both techniques in order to identify specific characteristics of the serves and consequently to give gUidelines for training and mastering especially on the new technique to coaches and players

Preliminary analysis of knee stress in Full Extension Landing

OBJECTIVE: This study provides an experimental and finite element analysis of knee-joint structure during extended-knee landing based on the extracted impact force, and it numerically identifies the contact pressure, stress distribution and possibility of bone-to-bone contact when a subject lands from a safe height. METHODS: The impact time and loads were measured via inverse dynamic analysis of free landing without knee flexion from three different heights (25, 50 and 75 cm), using five subjects with an average body mass index of 18.8. Three-dimensional data were developed from computed tomography scans and were reprocessed with modeling software before being imported and analyzed by finite element analysis software. The whole leg was considered to be a fixed middle-hinged structure, while impact loads were applied to the femur in an upward direction. RESULTS: Straight landing exerted an enormous amount of pressure on the knee joint as a result of the body's inability to utilize the lower extremity muscles, thereby maximizing the threat of injury when the load exceeds the height-safety threshold. CONCLUSIONS: The researchers conclude that extended-knee landing results in serious deformation of the meniscus and cartilage and increases the risk of bone-to-bone contact and serious knee injury when the load exceeds the threshold safety height. This risk is considerably greater than the risk of injury associated with walking downhill or flexion landing activities

Progress of key strategies in development of electrospun scaffolds: bone tissue

There has been unprecedented development in tissue engineering (TE) over the last few years owing to its potential applications, particularly in bone reconstruction or regeneration. In this article, we illustrate several advantages and disadvantages of different approaches to the design of electrospun TE scaffolds. We also review the major benefits of electrospun fibers for three-dimensional scaffolds in hard connective TE applications and identify the key strategies that can improve the mechanical properties of scaffolds for bone TE applications. A few interesting results of recent investigations have been explained for future trends in TE scaffold research