Development of a sports technology quality framework

Identifying tools and processes to effectively and efficiently evaluate technologies is an area of need for many sport stakeholders. This study aimed to develop a standardised, evidence-based framework to guide the evaluation of sports technologies. In developing the framework, a review of standards, guidelines and research into sports technology was conducted. Following this, 55 experts across the sports industry were presented with a draft framework for feedback. Following a two-round Delphi survey, the final framework consisted of 25 measurable features grouped under five quality pillars. These were 1) Quality Assurance & Measurement (Accuracy, Repeatability, Reproducibility, Specifications), 2) Established Benefit (Construct Validity, Concurrent Validity, Predictive Validity, Functionality), 3) Ethics & Security (Compliance, Privacy, Ownership, Safety, Transparency, Environmental Sustainability), 4) User Experience (Usability, Robustness, Data Representation, Customer Support & Training, Accessibility) & 5) Data Management (Data Standardisation, Interoperability, Maintainability, Scalability). The framework can be used to help design and refine sports technology in order to optimise quality and maintain industry standards, as well as guide purchasing decisions by organisations. It may also serve to create a common language for organisations, manufacturers, investors, and consumers to improve the efficiency of their decision-making relating to sports technology.

Ceramic-on-metal bearings in total hip replacement: whole blood metal ion levels and analysis of retrieved components

This study reports on ceramic-on-metal (CoM) bearings in total hip replacement. Whole blood metal ion levels were measured. The median increase in chromium and cobalt at 12 months was 0.08 microg/1 and 0.22 microg/1, respectively, in CoM bearings. Comparable values for metal-on-metal (MoM) were 0.48 microg/1 and 0.32 microg/1. The chromium levels were significantly lower in CoM than in MoM bearings (p = 0.02). The cobalt levels were lower, but the difference was not significant. Examination of two explanted ceramic heads revealed areas of thin metal transfer. CoM bearings (one explanted head and acetabular component, one explanted head and new acetabular component, and three new heads and acetabular components) were tested in a hip joint simulator. The explanted head and acetabular component had higher bedding-in. However, after one million cycles all the wear rates were the same and an order of magnitude less than that reported for MoM bearings. There were four outliers in each clinical group, primarily related to component malposition.

Comparison of wear of ultra-high molecular weight polyethylene acetabular cups against surface-engineered femoral heads

Alumina ceramic heads have been previously shown to reduce polyethylene wear in comparison to cobalt chrome (CoCr) heads in artificial hip joints. However, there are concerns about the brittle nature of ceramics. It is therefore of interest to investigate ceramic-like coatings on metallic heads. The aim of this study was to compare the friction and wear of ultra-high molecular weight polyethylene (UHMWPE) against alumina ceramic, CoCr, and surface-engineered ceramic-like coatings in a friction simulator and a hip joint simulator. All femoral heads tested were 28 mm diameter and included: Biolox Forte alumina, CoCr, arc evaporative physical vapour deposition (AEPVD) chromium nitride (CrN) coated CoCr, plasma-assisted chemical vapour deposition (PACVD) amorphous diamond-like carbon (aDLC) coated CoCr, sputter CrN coated CoCr, reactive gas controlled arc (RGCA) AEPVD titanium nitride (TiN) coated CoCr, and Graphit-iC coated CoCr. These were articulated against UHMWPE acetabular cups in a friction simulator and a hip joint simulator. Alumina and CoCr gave the lowest wear volumes whereas the sputter coated CrN gave the highest. Alumina also had the lowest friction factor. There was an association between surface parameters and wear. This study indicates that surface topography of surface-engineered femoral heads is more important than friction and wettability in controlling UHMWPE wear.

A comparison of the effects of concentric versus eccentric exercise on force and position sense at the human elbow joint

It is generally accepted that our sense of limb position and movement is provided, in part, by signals from muscle spindles, while the sense of muscle force derives from signals in tendon organs. Experiments are described here, using human subjects, in which the effects of eccentric and concentric exercise of elbow flexor muscles are compared on the sense of forearm position and the sense of tension in elbow flexors. Subjects were required to compress a preloaded spring with one arm, carrying out a concentric contraction in elbow flexors, then flexors of the other arm released the spring from compression and thereby carried out an eccentric contraction. The force of the spring was adjusted to be 20% maximum voluntary contraction (MVC), and each subject carried out a minimum of 120 contractions. Position sense was measured in blindfolded subjects by placing one forearm at a set angle and asking subjects to match it by positioning the other arm. Over 4 days postexercise, subjects placed the eccentrically exercised arms in a more extended position than the concentrically exercised arm suggesting that they thought the muscle was shorter than it actually was. In a force-matching task, subjects systematically undershot the target 10% MVC with their eccentrically exercised arm. Since it is known that eccentric exercise is associated with damage to muscle fibres, it is postulated that this leads to a disturbance of muscle receptors, the muscle spindles and tendon organs.

Who benefits from tricyclic antidepressants: a survey

To determine what patients are likely to benefit from treatment with a tricyclic antidepressant, the authors surveyed American researchers, teachers of psychiatry, general psychiatric practitioners, and foreign researchers. Areas of agreement were appreciable and can serve as an index of accepted community practice and as guidelines for teaching. Responses indicated that patients most likely to benefit from a tricyclic antidepressant are those with primary depression; early morning awakening; motor retardation; loss of appetite; weight loss; prior positive response to a tricyclic antidepressant; loss of interest in work or hobbies; sad, blue, or depressed feelings; improved mood in evening; and loss of interest in sex. Amitriptyline was preferred for agitated depressions, and imipramine was preferred for retarded depressions.