The immediate effects of hallux valgus orthoses: A comparison of orthosis designs.

BACKGROUND: Hallux valgus orthoses are available in a wide range of designs and materials, but the effects of their design on functional performance have not been fully investigated. RESEARCH QUESTION: This present study aims to comprehensively analyze the immediate effects of soft and semi-rigid hallux valgus orthoses on balance, plantar pressure, hallux valgus angle, and subjective sensations. METHODS: Sixteen female subjects have participated in the study, including 10 subjects with healthy feet and 6 with hallux valgus. Three conditions are tested, including in the barefoot and using two types of commercially available hallux valgus orthoses. The subjects participate in static and dynamic (walking) tests with the use of the Novel Pedar® system. The peak pressure values in the hallux, lateral toes, first metatarsophalangeal joint, 2-4th metatarsal heads, 5th metatarsal head, medial midfoot, lateral midfoot and rearfoot in the various foot conditions are examined and compared. The hallux valgus angle of each subject is measured based on their footprint. Their subjective feelings towards the orthoses are also evaluated. A repeated-measures analysis of variance, and independent-sample t-test are performed. RESULTS: The correction of the hallux valgus angle is statistically significant when the subjects with hallux valgus use the orthoses. In comparing the two types of orthoses, the use of the orthosis made of soft materials results in correction in the hallux valgus angle and higher wear comfort, and lower plantar pressure in hallux area. SIGNIFICANCE: The results provide insights into the design of hallux valgus orthoses, thus offering practical reference for the selection of hallux valgus orthosis with compromise between functional performance and wear comfort.

Hallux valgus orthosis characteristics and effectiveness: a systematic review with meta-analysis.

OBJECTIVE: The treatment effect of orthoses for hallux valgus (HV) is unclear with little interventional studies, the design involves multiple complex factors, and therefore a systematic analysis with meta-analysis is necessary. The objective of this systematic review and meta-analysis is to determine whether current foot orthoses are effective in treating HV. DESIGN: Systematic review with meta-analysis. DATA SOURCES: Electronic databases (PubMed, Scopus, Cinahl and Medline) are searched up to February 2020. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Interventional studies with content focus on HV orthosis design and any of the outcomes related to effectiveness for treating HV are included. The standardised mean differences are calculated. The risk of bias in included studies is assessed using the Cochrane Collaboration's risk of bias tools. RESULTS: In total, 2066 articles are identified. Among them, nine are selected and quality rated, and data are extracted and closely examined. A meta-analysis is conducted, where appropriate. The main causes of potential bias are missing outcome data and outcome measurement error. The results show that orthosis with a toe separator has the best effect of correcting the HV angle (standardised mean difference: 0.50, 95% CI: 0.189 to 0.803). CONCLUSION: The orthoses design with a toe separator or an element that allows for the foot anatomic alignment is critical for reducing the HV angle and relieving foot pain. The results contribute to a better selection of treatment for patients. PROSPERO REGISTRATION NUMBER: CRD42021260403.

Impact of postural variation on hand measurements: Three-dimensional anatomical analysis.

In this article, the impact of postural variations on hand anthropometry and distribution of skin strain ratios has been investigated. The literature suggests the glove fit directly affects hand functions. However, gloves currently manufactured based on a static posture failed to provide optimum fit. Workers often do not wear protective gloves due to discomfort caused by improper design, which increases the risk of hand injury. Full-color three-dimensional scans of the hands are captured with thirty healthy subjects (20 females, 10 males) to analyze the hand measurements and skin deformation with various postures. 42 of the 57 hand dimensions were found to have significant differences (p >0.05) related to hand posture. The skin strain ratios further suggest that the slant of the web space, dorsal-length and surface area should be increased, while the angles of the web space and length of the palm reduced to advance glove patterns. This research contributes to constructing gloves with optimum fit, performance, and comfort. Results show that in consideration of hand postures, the angle of the slant of web space between digits 2 and 5 and the finger length on the dorsal side should be increased, whilst the finger length on the palm side should be reduced in glove pattern design. Gloves currently constructed based on a splayed posture cannot provide a good fit. Consideration should be given to hand measurements in dynamic postures.

A Novel Bespoke Hypertrophic Scar Treatment: Actualizing Hybrid Pressure and Silicone Therapies with 3D Printing and Scanning.

The treatment of hypertrophic scars (HSs) is considered to be the most challenging task in wound rehabilitation. Conventional silicone sheet therapy has a positive effect on the healing process of HSs. However, the dimensions of the silicone sheet are typically larger than those of the HS itself which may negatively impact the healthy skin that surrounds the HS. Furthermore, the debonding and displacement of the silicone sheet from the skin are critical problems that affect treatment compliance. Herein, we propose a bespoke HS treatment design that integrates pressure sleeve with a silicone sheet and use of silicone gel using a workflow of three-dimensional (3D) printing, 3D scanning and computer-aided design, and manufacturing software. A finite element analysis (FEA) is used to optimize the control of the pressure distribution and investigate the effects of the silicone elastomer. The result shows that the silicone elastomer increases the amount of exerted pressure on the HS and minimizes unnecessary pressure to other parts of the wrist. Based on this treatment design, a silicone elastomer that perfectly conforms to an HS is printed and attached onto a customized pressure sleeve. Most importantly, unlimited scar treating gel can be applied as the means to optimize treatment of HSs while the silicone sheet is firmly affixed and secured by the pressure sleeve.

Customized Fabrication Approach for Hypertrophic Scar Treatment: 3D Printed Fabric Silicone Composite.

Hypertrophic scars (HS) are considered to be the greatest unmet challenge in wound and burn rehabilitation. The most common treatment for HS is pressure therapy, but pressure garments may not be able to exert adequate pressure onto HS due to the complexity of the human body. However, the development of three-dimensional (3D) scanning and direct digital manufacturing technologies has facilitated the customized placement of additively manufactured silicone gel onto fabric as a component of the pressure therapy garment. This study provides an introduction on a novel and customized fabrication approach to treat HS and discusses the mechanical properties of 3D printed fabric reinforced with a silicone composite. For further demonstration of the suggested HS therapy with customized silicone insert, silicone inserts for the finger webs and HS were additively manufactured onto the fabric. Through the pressure evaluation by Pliance X system, it proved that silicone insert increases the pressure exerted to the HS. Moreover, the mechanical properties of the additively manufactured fabric silicone composites were characterized. The findings suggest that as compared with single viscosity print materials, the adhesive force of the additively manufactured silicone and fabric showed a remarkable improvement of 600% when print materials with different viscosities were applied onto elevated fabric.