An optimal de Quervain's tenosynovitis splint with ergonomic thumb support and evenly distributed pressure.

Splinting is a conventional treatment for de Quervain's tenosynovitis (dQt). However, existing splints have problems such as excessive thermal discomfort and poor fit, which have been pointed out in previous studies. This study proposes a new functional splint consisting of both hard and soft materials with the aim of providing wear comfort with a good fit and sufficient stability of the injured hand. Thumb support of the splint is an important component that controls and protects the affected thumb. To develop an ergonomically shaped thumb support, 16 participants with dQt were recruited for three-dimensional (3D) scanning of their hands. The angles of the wrist and the curvature of the thumb were measured using computer software, and the results were used as a reference for the design of the prototype supports. Excessive pressure on particular regions, such as bony areas, may cause discomfort or pain. To ensure the wear comfort of the proposed splint, a finite element model (FEM) was built to simulate the wear process of the splint and hence to predict the pressure distribution exerted from the splint onto the hand of the wearer. The simulated results show that the pressure is evenly distributed over the hand, indicating that patients are likely to wear the proposed splint comfortably during their treatment period.

Case study on the effects of fit and material of sports gloves on hand performance.

Active and sports fashion in the high-end market focuses on fit, superior comfort and functional performance for various end-uses. However, the engineering design of sports gloves in relation to hand anthropometry measurements remains unclear. In this study, two types of ready-to-wear sport gloves, namely, war-gaming glove and hiking glove were purchased from the market. The glove dimensions, fabrication properties and the effect of glove fit on hand and finger dexterity were investigated. Thirty female individuals (20-29 years old) participated a series of hand performance tests and subjective perception rating assessments towards the gloves. Results indicated that the active range of motion of fingers, finger tactile sensitivity, gripping strength and ability to handle pegs and marbles decreased with the use of gloves compared with bare hands. The perceptions of comfort and ease of hand motions decreased with the increased of wear time. The glove fit in terms of finger length dimensions was significantly correlated with hand grip force. The glove fit in hand, wrist and finger circumference dimensions had significant impact on the ability to handle small objects. It is suggested that hand length, hand circumference, finger circumference and the ratio of finger length to palm length should be considered in the design and development of gloves to improve hand performance and comfort.

Effects of custom-made textile insoles on plantar pressure distribution and lower limb EMG activity during turning.

BACKGROUND: Turning during locomotion involves considerable changes of the body's center of mass and reduced stability, as well as lower limb kinematics and kinetics. However, many previous studies have been carried out to evaluate the effectiveness and applications of orthotic insoles as well as different types of orthotic materials in various clinical symptoms, which are focused primarily on straight line walking. Hence, the influence of custom-made insoles with the use of advanced three-dimensional spacer fabrics on biomechanics parameters in terms of plantar pressure distribution and lower limb electromyography during turning movement was studied. METHODS: Twelve subjects performed 180-degree turning at a speed 3.07-3.74 km/h for five successful trials under 3 insoles conditions: wearing traditional ethylene vinyl acetate insoles and two different spacer-fabricated insoles, with the plantar pressure and lower limb muscle activity collected simultaneously. Turning movement was broken down into 3 phases for analysis: Turning initiation, turn around and turn termination. RESULTS: There was a statistically significance difference in plantar pressure between the traditional insoles and the insoles made of a spacer fabric as the top layer (p < 0.05). Compared to the traditional insoles, insoles made of a spacer fabric reduced the peak pressure (>12 %) and pressure-time integral (>13 %) in toes, metatarsal head 1 and metatarsal heads 2-3 at turning initiation; (>15 %) and (>17 %) in medial midfoot and medial heel at turn around. Insoles with spacer fabrics on the top and middle layer reduced both pressure parameters (>18 %) in toes and MTH 1 at turn termination. In terms of muscle activities, insoles with two-layer spacer fabrics could lower maximum muscle activities of vastus lateralis (>16 %; p < 0.05) at turn around. CONCLUSIONS: Insoles with different fabrications could offer various pressure offloading patterns across the plantar and muscle activity changes while turning. Insoles with a spacer fabric on the top tend to reduce plantar pressure loading at different regions during turn initiation and turn around phases, while two-layer spacer-fabricated insoles may contribute to reduced vastus lateralis muscle activation during turn around. More importantly, this study provides a new dimension in the potential use of the textile-fabricated insoles which may widen the range of insole materials selection in the design and development of insoles so as to enhance the effectiveness of orthotic treatment.

Effects of indoor slippers on plantar pressure and lower limb EMG activity in older women.

Open-toe mule slippers are popular footwear worn at home especially by older women. However, their biomechanical effects are still poorly understood. The objective of this study is to therefore evaluate the physical properties of two typical types of open-toe mule slippers and the changes in plantar pressure and lower limb muscle activity of older women when wearing these slippers. Five walking trials have been carried out by ten healthy women. The results indicate that compared to barefoot, wearing slippers results in significant increases in the contact area of the mid-foot regions which lead to plantar pressure redistribution from metatarsal heads 2-3 and the lateral heel to the midfoot regions. However, there is no significant difference in the selected muscle activity across all conditions. The findings enhance our understanding of slipper features associated with changes in biomechanical measures thereby providing the basis of slipper designs for better foot protection and comfort.

2D and 3D anatomical analyses of hand dimensions for custom-made gloves.

Measuring hand anthropometric data for the development of good-fitting gloves is crucial. In pursuing higher accuracy in hand anthropometric measurements, scanning of hand surfaces with the aids of image analysis system to acquire measurements is an alternative to the manual methods. This study proposes a new hand measuring approach by using 2D and 3D scanning which are evaluated through comparisons of manual measurements. Thirty-three dimensions are measured by using (1) tape and calliper measurement; (2) 2D image analysis; (3) 3D image analysis based on ten captures; and (4) 3D image analysis based on three captures, respectively. Repeated-measures ANOVA, correlation analysis and RMSE are used to examine the results. The hand dimensions obtained from the four methods are highly linearly correlated. Hand data taken from 3D image analysis has no significant difference compared with manual measurements on hand and wrist circumferences, length and breadth dimension, regardless of the number of captures.