Use of 3D-Printed Heel Support Insoles Based on Arch Lift Improves Foot Pressure Distribution in Healthy People

The effectiveness of customised 3D-printed insoles on perceived pain, comfort, and completion time among frequent Park Runners: Study protocol for a pragmatic randomised controlled trial (The ZOLES RCT)

BACKGROUND

Running, a popular recreational activity, often leads to the experience of pain and discomfort among participants impacting performance and participation longevity. The ZOLES trial evaluates customised 3D-printed insoles for reducing pain in frequent parkrunners aged 35 and over. An innovative process of foot-scanning and responses to questions relating to size, pain, discomfort, and previous medical conditions are combined leading to the production of personalised 3D-printed orthotics.

METHODS

The ZOLES trial is a pragmatic, outcome assessor blinded, randomised, controlled, superiority trial involving 200 recreational runners, randomised to receive either customised 3D-printed insoles (ZOLES) or to a "do-as-usual" control group. The study follows a robust protocol, ensuring adherence to established guidelines for clinical trials, and is based at St Mary's University, Twickenham, London. The primary outcome is change in running-related pain over a 10-week period, assessed using an 11-point Numeric Rating Scale. Secondary outcomes include overall pain and discomfort, running-related comfort, 5k-completion time, time-loss due to injuries, running exposure, and adherence to the intervention. A balanced-block randomisation process is stratified by sex and parkrun location, and an intention-to-treat analyses will be employed on all outcomes in the primary trial report. The trial includes a 52-week post-market surveillance to assess long-term effects of the customised insoles.

DISCUSSION

The ZOLES trial aims to provide insights into real-world applicability and effectiveness of customised 3D-printed insoles in reducing running-related pain and enhancing overall running experience. Despite the limitation of a subjective primary outcome measure without participant blinding, the methodological rigor, including external outcome assessment and data handling, we anticipate results that are academically credible and applicable in real-world settings The results of this trial may have important implications for runners, clinicians, and the sports footwear industry, as evidence for the use of individualised insoles to improve running experience and prevention of pain may become evident.

TRIAL REGISTRATION

The trial was pre-registered at ClinicalTrials.gov with the trial identifier NCT06034210 on September 4, 2023, and publicly posted on September 13, 2023 (https://clinicaltrials.gov/study/NCT06034210).

PROTOCOL VERSION

Version 1, September 27, 2023.

Acute effects of athletic taping on arch deformity and plantar pressure in young female adults with flexible flatfoot

OBJECTIVE

This work aimed to explore the acute effects of athletic taping techniques on foot arch deformity and plantar pressure in young female adults with flexible flatfoot (FFT).

METHODS

Twenty young female adults with FFT were recruited in the current study. Each participant was randomly divided into two taping groups, namely, augmented low-dye (ALD) and modified low-dye (MLD). The foot arch deformity and plantar pressure were measured at baseline, after taping and after 20 min of walking. The foot arch deformity was determined based on navicular drop distance (NDD) and resting calcaneal stance position (RCSP).

RESULTS

Compared with baseline, the NDD values were significantly lower after taping. After 20 min of walking, ALD taping resulted in a lower NDD value than MLD (p < 0.001). ALD maintained a higher RCSP than baseline after 20 min of walking (p = 0.004). Furthermore, compared with baseline, medial midfoot force-time integration (p = 0.013) and contact area (p = 0.022) increased after taping with MLD, and peak pressure in the medial midfoot increased after walking for 20 min with MLD (p = 0.026). Peak pressure in the second to fifth toes significantly decreased after 20 min of walking with ALD compared with that after taping immediately (p = 0.002).

CONCLUSIONS

ALD and MLD taping could improve FFT arch deformity and plantar pressure distribution, prospectively changing peak pressure of the second to fifth toe area and medial midfoot after 20 min of walking, integrated contact area and force-time integration medial midfoot during walking in young female adults. Furthermore, ALD taping could improve FFT deformity more than using MLD after 20 min of walking. Thus, when treating FFT in young female adults, ALD taping should be considered adaptively to guide arch support production and correct midfoot pronation.

The Upper Limb Orthosis in the Rehabilitation of Stroke Patients: The Role of 3D Printing

Stroke represents the third cause of long-term disability in the world. About 80% of stroke patients have an impairment of bio-motor functions and over half fail to regain arm functionality, resulting in motor movement control disorder with serious loss in terms of social independence. Therefore, rehabilitation plays a key role in the reduction of patient disabilities, and 3D printing (3DP) has showed interesting improvements in related fields, thanks to the possibility to produce customized, eco-sustainable and cost-effective orthoses. This study investigated the clinical use of 3DP orthosis in rehabilitation compared to the traditional ones, focusing on the correlation between 3DP technology, therapy and outcomes. We screened 138 articles from PubMed, Scopus and Web of Science, selecting the 10 articles fulfilling the inclusion criteria, which were subsequently examined for the systematic review. The results showed that 3DP provides substantial advantages in terms of upper limb orthosis designed on the patient's needs. Moreover, seven research activities used biodegradable/recyclable materials, underlining the great potential of validated 3DP solutions in a clinical rehabilitation setting. The aim of this study was to highlight how 3DP could overcome the limitations of standard medical devices in order to support clinicians, bioengineers and innovation managers during the implementation of Healthcare 4.0.

3D Printing of Individual Running Insoles - A Case Study

Purpose

The study's starting point is to find a low-cost and best-fit solution for comfortable movement for a recreational runner with knee pain using an orthopedic device. It is a case study. The research aims to apply digitization, CAD/CAM tools, and 3D printing to create an individual 3D running insole. The objective is to incorporate flexible shape optimization would provide comfort reductions in foot plantar pressures in one subject with knee pain while running. The test hypothesis was if it is possible to make it from one material. For this purpose, we created a new digital workflow based on the Decision Tree method and analyzed pain and comfort scores during user testing of prototypes.

Patient and Methods

The input data were obtained during a professional examination by a specialist doctor in the orthopedic outpatient clinic in the motion laboratory (DIERS 4D Motion Lab, Germany) with the output of data on the proband's complex movement stereotype. Surface and volumetric data were obtained in the biomedical laboratory with the 3D scanner. We modified the digital 3D foot models in 3D mesh software, developed the design in SW Gensole (Gyrobot, UK), and finally incorporated the internal structure and the surface layer of the insole data of the knowledge from the medical examination, comfort analyses, and scientific studies findings.

Results

Four complete 3D-printed prototypes (n=4) with differences in density and correction elements were designed. All of them were fabricated on a 3D printer (Prusa i3 MK3S, Czech Republic) with flexible TPU material suitable for skin contact. The Participant tested each of them five times in the field during a workout and final insoles three months on the routine training.

Conclusion

A novel workflow was created for designing, producing, and testing full 3D-printed insoles. The product is fit for immediate use.

Design of Personalized Cervical Fixation Orthosis Based on 3D Printing Technology

The movement of the cervical spine should be restricted throughout the rehabilitation phase after it has been injured. Cervical orthosis is commonly utilized in clinical settings to guarantee cervical spine stability. However, to date, the investigations are limited to patient-specific cervical fixation orthoses. This study provides a new idea for making personalized orthoses. The CT data of the patient's cervical spine were collected, then mimics were used for reconstructing the skin of the cervical spine, the Geomagic Studio was used for surface fitting, the Inspire Studio was used for structural topology optimization, redundant structures were removed, the resulting orthotics were postprocessed, and finally, it was printed with a 3D printer. No signs of pain or discomfort were observed during the wearing. The cervical spine range of motion in flexion, extension, lateral flexion, and rotation is all less than 8° after using the device. Low cost, quick manufacturing time, high precision, attractive appearance, lightweight structure, waterproof design, and practical customized orthotics for patients are all advantages of 3D printing technology in the field of orthopedics. Many possible benefits of using 3D printing to build new orthotics include unique design, stiffness, weight optimization, and improved biomechanical performance, comfort, and fit. Personalized orthotics may be designed and manufactured utilizing 3D printing technology.

Effects of Custom-made Insoles on Plantar Biomechanics and Upper Extremity Muscle Performance

OBJECTIVE

To investigate the effectiveness of molding custom-made insoles for female patients with foot pain.

METHODS

The study included 20 patients whose insoles were prescribed according to biomechanical evaluations and molded by repositioning the subtalar joint in its neutral position using a simple set of tools. Plantar biomechanics were measured under the following conditions: static stand, walking at self-comfortable walking speed (CWS) barefoot, walking in patient owned running shoes, and walking in running shoes plus insoles. Each patient's upper arm isometric muscle strength and subjective feelings before and after the insole intervention were assessed.

RESULTS

The molded insoles increased plantar contact area both during static standing and walking at CWS compared to the barefoot condition. The insoles also had more evenly distributed plantar contact area and loading rate, with the changes in the medial arch area being most significant. Moreover, the custom-made insole intervention immediately increased maximum resistance and duration of bilateral upper arms, as well as improved foot comfort, especially at the medial arch area during single leg squat tests.

CONCLUSION

Molding custom-made insoles by repositioning the subtalar joint in its neutral position can be accomplished with a simple set of tools, making this method highly applicable for a majority of less developed regions. Insoles molded using this method are effective in immediately improving plantar biomechanics disorders and enhancing isometric upper muscle performance in female patients with foot pain.

A Three-Dimensional Printed Foot Orthosis for Flexible Flatfoot: An Exploratory Biomechanical Study on Arch Support Reinforcement and Undercut

The advancement of 3D printing and scanning technology enables the digitalization and customization of foot orthosis with better accuracy. However, customized insoles require rectification to direct control and/or correct foot deformity, particularly flatfoot. In this exploratory study, we aimed at two design rectification features (arch stiffness and arch height) using three sets of customized 3D-printed arch support insoles (R+U+, R+U-, and R-U+). The arch support stiffness could be with or without reinforcement (R+/-) and the arch height may or may not have an additional elevation, undercutting (U+/-), which were compared to the control (no insole). Ten collegiate participants (four males and six females) with flexible flatfoot were recruited for gait analysis on foot kinematics, vertical ground reaction force, and plantar pressure parameters. A randomized crossover trial was conducted on the four conditions and analyzed using the Friedman test with pairwise Wilcoxon signed-rank test. Compared to the control, there were significant increases in peak ankle dorsiflexion and peak pressure at the medial midfoot region, accompanied by a significant reduction in peak pressure at the hindfoot region for the insole conditions. In addition, the insoles tended to control hindfoot eversion and forefoot abduction though the effects were not significant. An insole with stronger support features (R+U+) did not necessarily produce more favorable outcomes, probably due to over-cutting or impingement. The outcome of this study provides additional data to assist the design rectification process. Future studies should consider a larger sample size with stratified flatfoot features and covariating ankle flexibility while incorporating more design features, particularly medial insole postings.

Design and Preliminary Validation of Individual Customized Insole for Adults with Flexible Flatfeet Based on the Plantar Pressure Redistribution

Flatfoot is a common musculoskeletal deformity. One of the most effective treatments is to wear individually customized plantar pressure-based insoles to help users change the abnormally distributed pressure on the pelma. However, most previous studies were divided only into several plantar areas without detailed plantar characteristic analysis. In this study, a new insole is designed which redistributes pressure following the analysis of characteristic points of plantar pressure, and practical evaluation during walking of subjects while wearing the insole. In total, 10 subjects with flexible flatfeet have participated in the performance of gait experiments by wearing flat insoles, orthotic insoles, and plantar pressure redistribution insoles (PPRI). The results showed that the stance time of PPRI was significantly lower than that of the flat insoles under slow gait. PPRI in the second to third metatarsal and medial heel area showed better unloading capabilities than orthotic insoles. In the metatarsal and heel area, the PPRI also had its advantage in percentage of contact area compared to flat insole and orthotic insole. The results prove that PPRI improves the plantar pressure distribution and gait efficiency of adults with flexible flatfeet, and can be applied into clinical application.