Search Results (76)

Background and Objectives: Three-dimensional (3D) scanning is increasingly utilized in medical practice, from orthotics to surgical planning. However, traditional hand measurement techniques remain inconsistent and prone to human error and are often time-consuming. This research evaluates the practicality of a commercial 3D scanning method by comparing the accuracy of scans conducted by two user groups. Materials and Methods: This study evaluated the following two groups: an experimental group (n = 45) and a control group (n = 42). A total of 261 hand scans were captured using the Structure Sensor Pro 3D scanner for iPad (Structure, Boulder, CO, USA). The scans were then evaluated using Meshmixer software (version 3.5.474), analyzing key parameters, such as surface area, volume, number of vertices, and triangles, etc. Furthermore, a digital literacy test and a user experience survey were conducted to support a more comprehensive evaluation of participant performance within the study. Results: The experimental group outperformed the control group on all measured parameters, including surface area, volume, vertices, triangle, and gap count, with large effect sizes observed. User experience data revealed that participants in the experimental group rated the 3D scanner significantly higher across all dimensions, particularly in ease of use, excitement, supportiveness, and practicality. Conclusions: A short 15 min training session can promote scan reliability, demonstrating that even minimal instruction improves users’ proficiency in 3D scanning, fundamental for supporting clinical accuracy in diagnosis, surgical planning, and personalized device manufacturing Full article

Nowadays, Fused Filament Fabrication (FFF) 3D printing offers promising opportunities for the customized manufacturing of ankle–foot orthoses (AFOs) targeted towards rehabilitation purposes. Polypropylene (PP) represents an ideal candidate in orthotic applications due to its light weight and superior mechanical properties, offering an excellent balance between flexibility, chemical resistance, biocompatibility, and long-term durability. However, Additive Manufacturing (AM) of AFOs based on PP remains a major challenge due to its limited bed adhesion and high shrinkage, especially for making large parts such as AFOs. The primary innovation of the present study lies in the optimization of FFF 3D printing parameters for the fabrication of functional, patient-specific orthoses using PP, a material still underutilized in the AM of medical devices. Firstly, a thorough thermomechanical characterization was conducted, allowing the implementation of a (thermo-)elastic material model for the used PP filament. Thereafter, a Taguchi design of experiments (DOE) was established to study the influence of several printing parameters (extrusion temperature, printing speed, layer thickness, infill density, infill pattern, and part orientation) on the mechanical properties of 3D-printed specimens. Three-point bending tests were conducted to evaluate the strength and stiffness of the samples, while additional tensile tests were performed on the 3D-printed orthoses using a home-made innovative device to validate the optimal configurations. The results showed that the maximum flexural modulus of 3D-printed specimens was achieved when the printing speed was around 50 mm/s. The most significant parameter for mechanical performance and reduction in printing time was shown to be infill density, contributing 73.2% to maximum stress and 75.2% to Interlaminar Shear Strength (ILSS). Finally, the applicability of the finite element method (FEM) to simulate the FFF process-induced deflections, part distortion (warpage), and residual stresses in 3D-printed orthoses was investigated using a numerical simulation tool (Digimat-AM^®). The combination of Taguchi DOE with Digimat-AM for polypropylene AFOs highlighted that the 90° orientation appeared to be the most suitable configuration, as it minimizes deformation and von Mises stress, ensuring improved quality and robustness of the printed orthoses. The findings from this study contribute by providing a reliable method for printing PP parts with improved mechanical performance, thereby opening new opportunities for its use in medical-grade additive manufacturing. Full article

Background: Charcot-Marie-Tooth (CMT) disease is a hereditary motor and sensory neuropathy that affects foot morphology and gait patterns, potentially leading to abnormal plantar pressure distribution. This systematic review synthesizes the existing literature examining plantar pressure characteristics in CMT patients. Methods: A comprehensive search was conducted across PubMed, Scopus, and Web of Science databases. Risk of bias was assessed using the Newcastle–Ottawa Scale. Results: Six studies comprising 146 patients were included. Four studies employed dynamic baropodometry, and two used in-shoe pressure sensors to evaluate the main plantar pressure parameters. The findings were consistent across different populations and devices, with a characteristic plantar-pressure profile of marked midfoot off-loading with peripheral overload at the forefoot and rearfoot, often accompanied by a lateralized center-of-pressure path and a prolonged pressure–time exposure. These alterations reflect both structural deformities and impaired neuromuscular control. Interventional studies demonstrated a load redistribution of pressure after corrective surgery, though residual lateral overload often persists. Conclusions: Plantar pressure mapping seems to be a valuable tool to identify high-pressure zones of the foot in order to personalize orthotic treatment planning, to objectively monitor disease progression, and to evaluate therapeutic efficacy. Further longitudinal studies with standardized protocols are needed to confirm these results. Full article

Orthotics are often used to support the metacarpophalangeal joint (MCPj) in horses recovering from soft tissue injury; however, their effect on the MCPj biomechanics remain largely underexplored. The MCPj moves primarily in the sagittal plane, flexing during the swing phase and extending during the stance phase. The suspensory ligament and flexor tendons act as biological springs resisting MCPj extension. Injuries to these structures are common and, although early mobilization promotes their healing, controlled loading may be beneficial during rehabilitation. This study aims to evaluate the efficacy of a semirigid orthotic in limiting the MCPj extension and the MCPj range of motion, and its influence on the MCPj kinematics. Twelve healthy horses were equipped with portable inertial sensors on the distal limb. The MCPj extension and the MCPj range of motion were assessed during walking and trotting without the orthotic (S0) and with the orthotic using two different support settings (S1 and S4). Data were evaluated for normality and homoscedasticity. A Student t-test was used to compare the MCPj angle pattern of the two forelimbs of each horse at the baseline. Data were analysed using one-way ANOVA to compare the mean values across conditions, followed by paired t-tests for post-hoc comparison (significance set at p < 0.05). The results showed significant reductions in both the MCPj extension and the MCPj range of motion, with the greatest restriction occurring at the highest support setting. These results suggest that the semirigid orthotic limits the MCPj movement in the sagittal plane and consequently the load on the suspensory ligament and flexor tendons. Therefore, this orthotic device is an effective tool during rehabilitation for forelimb tendon and ligament injuries. Full article

We developed an optoelectronic sensor capable of quantifying in-plane rotational and linear displacements between two parallel surfaces. The sensor utilizes a photo detector to capture the intensity of red (R), green (G), blue (B), and clear (C, broad visible spectrum) light reflected from a color gradient wheel on the opposing surface. Variations in reflected R, G, B and C light intensities, caused by displacements, were used to predict linear and rotational motion via a polynomial regression algorithm. To train and validate this model, we employed a custom-built positioning stage that produced controlled displacement and rotation while recording corresponding changes in light intensity. The reliability of the predicted linear and rotational displacement results was evaluated using two different color gradient wheels: a wheel with changing color hue, and another wheel with changing color hue and saturation. Benchtop experiments demonstrated high predictive accuracy, with coefficients of determination (R²) exceeding 0.94 for the hue-only wheel and 0.92 for the hue-and-saturation wheel. These results highlight the sensor’s potential for detecting shear displacement and rotation in footwear and wearable medical devices, such as orthotics and prostheses, enabling the detection of slippage, overfitting, or underfitting. This capability is particularly relevant to clinical conditions, including diabetic neuropathy, flat feet, and limb amputations. Full article

Background/Objectives: This review analyzes the effects of invasive and non-invasive methods of knee joint unloading on knee loading, employing a biomechanical model to evaluate their impact. Methods: PubMed, Web of Science, Cochrane, and Scopus were searched up to 15 May 2024 to identify eligible clinical studies evaluating Joint Space Width, Cartilage Thickness, the Western Ontario and McMaster Universities Osteoarthritis Index, the Knee Injury and Osteoarthritis Outcome Score system, Gait velocity, Peak Knee Adduction Moment, time to return to sports and to work, ground reaction force, and the visual analogue scale pain score. A second search was conducted to select a biomechanical model that could be parametrized, including the modifications that each treatment would impose on the knee joint and was capable of estimate joint loading to compare the effectiveness of each method. Results: Analyzing 28 studies (1652 participants), including 16 randomized clinical trials, revealed significant improvements mainly when performing knee joint distraction surgery, increasing Joint Space Width even after removal, and high tibial osteotomy, which realigns the knee but does not reduce loading. Implantable shock absorbers are also an attractive option as they partially unload the knee but require further investigation. Non-invasive methods improve biomechanical indicators of knee joint loading; however, they lack quantitative analysis of cartilage volume or Joint Space Width. Conclusions: Current evidence indicates a clear advantage in knee joint unloading methods, emphasizing the importance of adapted therapy. However, more extensive research, particularly using non-invasive approaches, is required to further understand the underlying knee joint loading mechanisms and advance the state of the art. Full article

Background: Iliotibial band syndrome (ITBS) through the tensor fascia latae (TFL) is a well-known pathology among runners whose etiology is not completely clear, nor is the effectiveness of plantar insoles for different types of feet known well enough for them to be considered a possible approach for this issue. Objective: to understand how foot type and foot orthotics may influence the electromyographic (EMG) activity of the TFL. Methods: A total of 41 healthy recreational runners (mean age 32.66 ± 3.51) were recruited for the present cross-sectional study, categorizing them as neutral (NEUg = 15), supinators (SUPg = 15), and pronators (PROg = 11) according to the foot postural index, over a period of 11 months. The EMG of the TFL was measured using a surface electromyograph device while they ran on a treadmill at a constant speed of 9 km/h for 3 min, randomly using supinating (SUP), pronating (PRO), or heel lift (TAL) insoles of 5 mm each one, compared to the baseline condition (SIN). The intraclass correlation coefficient (ICC) was performed to check the reproducibility of the tests, pairwise comparisons with Bonferroni adjustment were made, and to test the differences between measurements, the Friedman test was performed. Results: The Shapiro–Wilk test indicated a normal distribution of the sample (p > 0.05). Almost all obtained results showed a “perfect reproducibility” close to one; a significant statistical increase was observed in the mean EMG values from NEUg (87.58 ± 4.81 mV) to SUPg (97.17 ± 4.3 mV) (p < 0.05) during SIN+ basal condition. Additionally, there was a statistical reduction from SIN (87.58 ± 4.81 mV) vs. PRO (74.69 ± 3.77 mV) (p < 0.001) in NEUg and from SIN (97.17 ± 4.3 mV) vs. PRO (90.96 ± 4 mV) (p < 0.001) in SUPg. Conclusions: The SUPg exhibited increased activation of TFL fibers compared to the NEUg, likely due to the biomechanical demands associated with a supinated foot type. In contrast, the use of PRO appeared to promote relaxation of the TFL fibers by inducing internal rotation of the lower limb. Based on these preliminary results from a cross-sectional study in a healthy population, it is recommended to assess foot type when addressing ITBS and to consider the use of PRO as a complementary therapeutic strategy alongside conventional treatments. Full article

Background: This study compared performance-based function and self-report function in lower-limb prosthesis users. Methods: Twenty-two lower-limb prosthesis users (aged 52.1 ± 14.2) were administered the Orthotic Prosthetic User Survey (OPUS) Lower Extremity Functional Status (LEF), Satisfaction With Devices (SWD), alongside the Godin Leisure-Time Exercise Questionnaire (GLTQ), Timed Up and Go (TUG) test, two-minute walk test (2MWT), and six-minute walk test (6MWT). Body composition and standing postural sway displacement and velocity were also measured. Pearson’s Product Moment coefficients were used to assess relationships between the OPUS and other outcome variables. ANOVAs were used to identify differences in all outcome variables between lower unilateral (LU) and all other (AO) amputees. Results: There was a moderate correlation between LEF and center of pressure (CoP) path length with eyes open (r₍₁₉₎ = −0.43, p = 0.048) and eyes closed (r₍₁₉₎ = −0.43, p = 0.049). While the relationship between LEF and TUG was significant (r₍₂₀₎ = −0.49, p = 0.021), this was not so with SWD and TUG (r₍₂₀₎ = −0.17, p = 0.456). Both the 2MWT (r₍₂₀₎ = 0.48, p = 0.023) and 6MWT (r₍₂₀₎ = 0.47, p = 0.028) were moderately correlated with LEF. GLTQ was significantly correlated with LEF (r₍₂₀₎ = 0.70, p = 0.001). The LU group outperformed the AP group during the TUG and 6MWT (p < 0.05). LU group scored significantly higher on LEF compared to the AO group (p < 0.05). The reliability of LEF between the measurement on day 1 (54.3 ± 12.0) and day 2 (53.6 ± 12.8) was high (α = 0.94). Conclusions: This study provides an insight into associations of balance and self-reported function in lower limb prosthesis users. Future work can target rehabilitation strategies to address challenges faced by multiple limb prosthesis users. Full article

Athletic Tape is widely used as an immediate and cost-effective intervention for flexible flat feet, offering a practical alternative to orthotic devices and exercise therapies. This study aimed to compare the effects of low-dye and anti-pronation taping (elastic and inelastic) on ankle strength, gait parameters, and balance control in women with flexible flat feet. Thirty women were evaluated under four conditions: no taping, low-dye taping, elastic anti-pronation taping, and inelastic anti-pronation taping. Each condition was tested at 3-day intervals. Outcome measures included ankle muscle strength, step length, stride length, balance control ability assessed using the Romberg and limits of stability tests. Repeated-measures analysis of variance and post hoc least significant difference analyses were used to determine statistical significance. Additionally, effect sizes (η²) were calculated for the primary outcomes. Dorsiflexion strength significantly improved with elastic taping (p < 0.05). Step length increased with both elastic and inelastic taping, whereas stride length improved only with elastic taping. All taping methods significantly reduced the limits of stability compared with the no-taping condition (p < 0.05). Athletic Tape interventions, especially elastic anti-pronation taping, may reduce excessive foot pronation and improve ankle strength and gait performance in women with flexible flat feet. Full article

Background: Early-onset scoliosis (EOS) is a severe spinal deformity that can compromise thoracic development and pulmonary function if left untreated. While Mehta casting is widely used to manage deformity non-surgically in young children, its effects on spinal and thoracic growth remain underexplored. Methods: In this retrospective case series, 15 children with EOS underwent serial elongation–derotation–flexion (EDF) Mehta casting. Radiographic assessments were performed pre-treatment, post-casting, and at follow-up, including measurements of Cobb angle, rib–vertebral angle difference (RVAD), Th1–Th12 spinal length, coronal chest width (CCW), and space available for lung (SAL). Growth rates were estimated based on the duration of treatment. Correlation analyses were conducted to examine associations between baseline deformity and structural outcomes. Results: Serial casting reduced the mean Cobb angle by 22.2° and RVAD by 15.5°. During treatment, measurable increases were observed in Th1–Th12 length (mean: 2.93 cm), CCW (1.12 cm), SAL-L (2.60 cm), and SAL-R (2.98 cm). Estimated annual growth was significantly greater in children with lower initial Cobb and RVAD values. In contrast, total casting duration showed no consistent correlation with growth outcomes. Conclusions: Mehta casting is effective not only in correcting spinal deformity but also in supporting thoracic and axial growth in children with EOS. Early application in flexible, less severe curves may optimize structural outcomes and preserve thoracic development during early growth. Full article

Integrating bioinspired design and additive manufacturing into engineering education fosters innovation to meet the growing demand for accessible, personalized assistive technologies. This paper presents the outcomes of an international course, “3D Prosthetics and Orthotics”, offered to undergraduate students in the Biomimetic program at Westfälische Hochschule (Germany), in collaboration with the 3D Orthotics and Prosthetics Laboratory at the Federal University of São Paulo—UNIFESP (Brazil). The course combined theoretical and hands-on modules covering digital modeling (CAD), simulation (CAE), and fabrication (CAM), enabling students to develop bioinspired assistive devices through a Project-based learning approach. Working in interdisciplinary teams, students addressed real-world rehabilitation challenges by translating biological mechanisms into engineered solutions using additive manufacturing. Resulting prototypes included a hand prosthesis based on the Fin Ray effect, a modular finger prosthesis inspired by tendon–muscle antagonism, and a cervical orthosis designed based on stingray morphology. Each device was digitally modeled, mechanically analyzed, and physically fabricated using open-source and low-cost methods. This initiative illustrates how biomimetic mechanisms and design can be integrated into education to generate functional outcomes and socially impactful health technologies. Grounded in the Mao3D open-source methodology, this experience demonstrates the value of combining nature-inspired principles, digital fabrication, Design Thinking, and international collaboration to advance inclusive, low-cost innovations in assistive technology. Full article

This paper presents a wearable, open-source system that combines electromyography (EMG) and functional electrical stimulation (FES) to restore hand function in individuals with disabilities caused by cervical spinal cord injuries or stroke. The device captures electrical signals produced during volitional muscle contractions and analyzes them to interpret the user’s intent to move. This information is then used to stimulate impaired muscles, promoting improved hand function and rehabilitation. We detail the design, prototyping, and testing of the system, emphasizing its modularity, affordability, and accessibility. Hardware and software, along with 3D-printable components, are shared via GitHub to enable replication and customization by professionals and makers. The system serves as both an orthotic device for enhancing grasping ability and a therapeutic tool for rehabilitating hemiparetic hands, with potential for broader applications. By addressing cost, customization, and accessibility barriers, this initiative promotes collaboration and further innovation in rehabilitation technologies, advancing the development of affordable, user-centered solutions for individuals with disabilities. Full article

Additive manufacturing (AM), also referred to as three-dimensional printing/printed (3DP), has emerged as a transformative approach in the current design and manufacturing of various biomaterials for the restoration of damaged tissues inside the body. This advancement has greatly aided the development of customized biomedical devices including implants, prosthetics, and orthotics that are specific to the patients. In tissue engineering (TE), AM enables the fabrication of complex structures that promote desirable cellular responses in the regeneration of tissues. Since the choice of biomaterials plays a vital role in scaffold performance as well as cellular responses, meticulous material selection is essential in optimizing the functionality of scaffolds. These scaffolds often possess certain characteristics such as biodegradability, biocompatibility, biomimicry, and porous structure. To this end, polymers such as chitosan, collagen, alginate, hyaluronic acid, polyglycolic acid, polylactic acid, and polycaprolactone have been extensively investigated in the fabrication of tissue-engineered scaffolds. Furthermore, combinations of biomaterials are also utilized to further enhance the scaffolds’ performance and functionality. This review discusses the principle of AM and explores recent advancements in AM technologies in the development of TE and regenerative medicine. In addition, the applications of 3DP, polymer-based scaffolds will be highlighted. Full article

The lack of social acceptability for wearable devices such as orthopedic foot orthoses can lead to irregular usage and missed health benefits, as shown in prior studies. While AI-generated designs have been explored for prototyping aesthetic hand orthoses, their impact on social acceptability, particularly for foot orthoses, remains unknown. The current state of research is limited, as no empirical evidence exists on whether AI-designed orthoses influence acceptance, nor has the role of customized generative pre-trained transformers (GPTs) and specific prompting strategies been examined in this context. To address these gaps, we conducted two mixed-methods studies to investigate (1) the impact of AI-generated orthosis designs on social acceptability compared to existing orthopedic products and development concepts and (2) how a customized GPT and different prompt keywords influence acceptance. Our results show that AI-generated designs significantly enhance social acceptance across orthotic categories. Furthermore, we found that personalized GPTs and targeted prompt keywords significantly influence user perception. Overall, our findings highlight the potential of using AI to create socially acceptable design solutions for wearable technology and offer new applications for future smart devices. We contribute to generative AI in product design and provide concrete recommendations for optimizing prompting strategies to enhance social acceptance. Full article

Background and Objectives: In-toeing and out-toeing gait are rotational deformities commonly observed in children with neuromuscular conditions. These gait abnormalities often result from internal tibial torsion, increased femoral anteversion, and metatarsus adductus. This study was conducted to create a comprehensive evaluation of the effectiveness of lower extremity orthotics as a non-operative treatment option, given their regular use in clinical settings. The aim of this literature review was to understand the efficacy of various orthotic devices in correcting rotational deformities in the transverse plane, thereby improving ambulation stability and 3D joint motion. Materials and Methods: Literature published after 1 January 1990 was reviewed, utilizing databases such as CENTRAL (Wiley), CINAHL (EBSCO), Medline (OVID), Scopus (Elsevier), and Web of Science (Clarivate). In totality, 13 studies were included, evaluating 365 participants with neuromuscular conditions using various orthotic devices. Results: Among these studies, two were randomized control trials (Level 1), nine were quasi-experimental studies (Level 2), and two were case studies (Level 4). Quality assessment determined that 69% of the included studies had a low risk of bias, while 31% demonstrated a moderate risk. Compression garments and rotational systems showcased the greatest change in proximal lower extremity rotation at 19.73° ± 1.57 and 24.13° ± 8.49, respectively. The most significant difference in foot progression angle is through the use of rotational systems, 19° ± 26.87. Conclusions: In a short-term treatment, children with neuromuscular disorders exhibiting in-toeing or out-toeing gait may benefit from different types of orthoses. Compression garments may aid joint alignment and enhance proprioception, rotational systems correct alignment with precise adjustability, AFOs that achieve effective stabilization can deliver benefits in the transverse plane, and foot orthotics may be appropriate for mild gait abnormality management. Full article