Philip Sewell

Additive manufacturing (AM) is increasingly applied to lower-limb prosthetic sockets, offering faster production, lower cost, and improved customisation. Multi-material additive manufacturing (MMAM) enables rigid and flexible regions to be combined in a single socket, potentially improving load distribution and user comfort. However, research on MMAM remains limited and is distributed across engineering, biomechanical, and clinical disciplines. A scoping review was conducted following PRISMA-ScR guidelines. Five databases (PubMed, Scopus, IEEE Xplore, Web of Science, and EBSCO) were searched for English-language publications from 2010 to 2024. Studies reporting the use of AM in the fabrication of lower-limb prosthetic sockets were included. Data were extracted and synthesised through thematic categorisation. Forty-six studies met the inclusion criteria. Five themes were identified: mechanical performance and structural enhancement (n = 18), comfort and fit optimisation (n = 11), AM parameter optimisation (n = 8), comparisons with conventional sockets (n = 7), and exploratory designs (n = 2). Most research addressed mechanical reinforcement and parameter effects. MMAM applications remained largely at the prototype stage. AM is a rapidly developing approach to lower-limb prosthetic socket fabrication. Evidence for MMAM remains preliminary, underscoring the need for standardised testing, reproducible workflows, and early clinical evaluation to support its translation into rehabilitation practice.Additive manufacturing (AM) is increasingly applied to lower-limb prosthetic sockets, offering faster production, lower cost, and improved customisation. Multi-material additive manufacturing (MMAM) enables rigid and flexible regions to be combined in one socket, potentially improving load distribution and user comfort. However, research on MMAM remains limited and distributed across engineering, biomechanical, and clinical research. A scoping review was conducted following PRISMA-ScR guidelines. Five databases (PubMed, Scopus, IEEE Xplore, Web of Science, and EBSCO) were searched for English-language publications from 2010 to 2024. Studies reporting AM in the fabrication of lower-limb prosthetic sockets were included. Data were extracted and synthesised using thematic categorisation. Forty-six studies met the inclusion criteria. Five themes emerged: mechanical performance and structural enhancement (n=18), comfort and fit optimisation (n=11), AM parameter optimisation (n=8), comparisons with conventional sockets (n=7), and exploratory designs (n=2). Most research focused on mechanical reinforcement and parameter effects, while MMAM applications remained largely at the prototype stage. AM is a rapidly developing approach to lower-limb prosthetic socket fabrication. Evidence for MMAM remains preliminary, highlighting the need for standardised testing, reproducible workflows, and early clinical evaluation to support translation into rehabilitation practice.

Background: This research paper presents a comprehensive parametric study that investigates the influence of various 3D printing parameters on the mechanical properties of a pediatric prosthetic keel using coupon samples. Objective: To analyze how 3D printing parameters impact upon on 2 crucial mechanical properties: stiffness and hysteresis. Methods: Key 3D printing parameters including the amount of continuous carbon fiber layers, fiber distribution, and matrix fill pattern, are systematically varied, and mechanically tested through compression to analyze the results. Results: The results demonstrate the substantial impact that printing parameters have on the mechanical characteristics of 3D-printed pediatric prosthetic feet. Notably, the selection of these parameters for the prosthetic keel plays a pivotal role in shaping the overall performance and functionality of the prosthetic foot, emphasizing the need for precise parameter optimization in pediatric prosthetic design, if 3D printing is the manufacturing process. Conclusions: The findings of this study contribute to a better understanding of the manufacturing process for pediatric prosthetic feet via 3D printing and offer valuable insights for optimizing their design. By identifying the ideal combination of 3D printing parameters that yield the desired stiffness and minimize hysteresis, we aim to enhance the performance and comfort of pediatric prosthetic devices, ultimately improving the quality of life for young users.

Sports and recreational activities offer physical and psychological benefits to children with limb absence. Understanding what facilitators and barriers exist for the participation in sports and physical activity is vital to aid stakeholders to continue enabling facilitators and develop means to tackle existing barriers so that all children with lower-limb absence can participate in sport and physical activity as they wish. The aim of this systematic review was to identify facilitators and barriers that children with lower-limb absence experience when wanting to participate in sports and physical activity. Systematic review. Five databases were used to identify the literature relating to facilitators and barriers to sports and physical activity for children with lower-limb absence. These were Medline, Scopus, Cochrane, SPORTDiscus, and CINAHL. Google scholar was used as a secondary source. The review followed the “Preferred Reporting Item for Systematic Reviews and Meta-Analysis” guidelines. The review identified 10 articles for inclusion that met predefined inclusion criteria. The identified peer-review articles date from 1999 to 2021. The number of published articles steadily increases up to 2010 and then increase rapidly from 2016 to 2021. The results show although there are facilitators for sports participation for children with limb absence, there are many barriers which continue to hinder many children from participating in sports and physical activity. Facilitators that exist include advancements in prosthetic design and technology, increased opportunities, and physical and social benefits. Barriers that were reported include prosthesis failure, stigma, and high costs.

Background: Involving patients and members of the public, together with researchers, in decisions about how studies are designed and conducted can create a study that is more person‐centred. The aim of this consultation process was to explore ways of designing a study which takes the person into consideration for the randomized clinical study entitled ‘Biomechanical Effects of Manual Therapy—A Feasibility Study’ using the novel approach of usability testing.Design: Patient and public volunteers were sought with experience of low back pain. Volunteers were invited to participate in usability testing (a physical walkthrough) of the proposed study method. This was followed by a discussion of areas where usability testing could not be used, such as recruitment strategies, continuity of participant care and dissemination of results. Resulting feedback was considered by the research team and alterations to the original study method were incorporated, provided the research questions could be answered and were practical within the resources available.Results: Additional recruitment strategies were proposed. Alterations to the study included reduction in study time burden; completion of study paperwork in a quieter location; continuity of participant care after the study; and methods of dissemination of overall study results to participants.Conclusion: The consultation process used the unique method of usability testing, together with a post‐usability discussion, and resulted in alterations to the future study which may facilitate making it more person‐centred.Patient and Public Contribution: Patients and public developed the future study design but did not participate in manuscript preparation.

Background: Stakeholder involvement includes not just patients and public, but also those delivering treatment for example clinicians and students. Each stakeholder brings unique experiences to the process. The aim of this stakeholder exercise was to explore readability and understanding of the trial material for the future trial to be conducted by the authors: Biomechanical Effects of Manual Therapy—A Feasibility Study.Design: Volunteers from identified stakeholder groups were provided with trial material which included the information sheet, consent form, questionnaires and home management booklet. They provided feedback on content (readability, understanding) and style (font, layout). An additional document was provided with genres of pictures to choose the most appropriate style to be used in the booklet.Readability formulas were used to calculate reading age before and after feedback to objectively measure ease of reading.Results: The public group provided a layperson's perspective to clarify the information sheet for patients, whereas practitioner and intern groups indicated where information could be clarified. The reading age of all documentation decreased following feedback; however, templated sections of the documentation did not. The majority (87%) of volunteers chose coloured classic cartoons for the booklet.Conclusion: This process highlighted the importance of involving different stakeholder groups in the development of research materials as each group made a unique contribution. Readability and understanding of the trial material were improved, feeding back into the consent process contributing towards fully informed consent.Patient or Public Contribution: Public helped develop materials for a future trial but not with manuscript preparation.

The current method of prescribing composite running-specific energy-storing-and-returning feet is subjective and is based only on the amputee’s static body weight/mass. The aim was to investigate their dynamic characteristics and create a relationship between these dynamic data and the prescription of foot. Experimental Assessment. This article presents the modal analysis results of the full range of Össur Flex-Run^™ running feet that are commercially available (1LO–9LO) using experimental modal analysis technique under a constant mass at 53 kg and boundary condition. It was shown that both the undamped natural frequency and stiffness increase linearly from the lowest to the highest stiffness category of foot which allows for a more informed prescription of foot when tuning to a matched natural frequency. The low damping characteristics determined experimentally that ranged between 1.5% and 2.0% indicates that the feet require less input energy to maintain the steady-state cyclic motion before take-off from the ground. An analysis of the mode shapes also showed a unique design feature of these feet that is hypothesised to enhance their performance. A better understanding of dynamic characteristics of the feet can help tune the feet to the user’s requirements in promoting a better gait performance. The dynamic data determined from this study are needed to better inform the amputees in predicting the natural frequency of the foot prescribed. The amputees can intuitively tune the cyclic body rhythm during walking or running to match with the natural frequency. This could eventually promote a better gait performance.

Traditional shoulder range of movement (ROM) measurement tools suffer from inaccuracy or from long experimental setup times. Recently, it has been demonstrated that relatively low-cost wearable inertial measurement unit (IMU) sensors can overcome many of the limitations of traditional motion tracking systems. The aim of this study is to develop and evaluate a single IMU combined with an electromyography (EMG) sensor to monitor the 3D reachable workspace with simultaneous measurement of deltoid muscle activity across the shoulder ROM. Six volunteer subjects with healthy shoulders and one participant with a ‘frozen’ shoulder were recruited to the study. Arm movement in 3D space was plotted in spherical coordinates while the relative EMG intensity of any arm position is presented graphically. The results showed that there was an average ROM surface area of 27291 ± 538 deg² among all six healthy individuals and a ROM surface area of 13571 ± 308 deg² for the subject with frozen shoulder. All three sections of the deltoid show greater EMG activity at higher elevation angles. Using such tools enables individuals, surgeons and physiotherapists to measure the maximum envelope of motion in conjunction with muscle activity in order to provide an objective assessment of shoulder performance in the voluntary 3D workspace.

The tidal energy within the seas surrounding the United Kingdom offers a vast renewable resource that is perfectly predictable over long timescales. Currently, the bulk of tidal energy research is focused on developing large devices for the most resource rich locations, which can be many miles from populated areas. The potential of small-scale tidal power from sub-optimal shallow water sites, close to populated regions, has so far been overlooked. Such generation would benefit from reduced transmission losses and contribute towards a distributed electricity grid, helping to overcome the variability of other renewables. This work presents a novel method for generating hydropower using the water hammer effect: a pressure surge that can occur in a pipeline following the abrupt closure of a valve. These pressure surges are used to produce vertical oscillations from horizontally flowing water, allowing power to be generated in a manner analogous to a wave energy convertor. A non-optimised scale model was found experimentally to have a peak available power density of 1.08 ± 0.25 kW/m² and a mean of 0.07 ± 0.02 kW/m². In comparison, the MCT SeaGen S (arguably the most well-developed tidal energy device) is capable of generating 3.18 kW/m². With further development, a water hammer device may therefore be useful for generating pico-scale tidal power in slow, shallow water flows.

In this paper the validation of a rig capable of simulating the dynamic response of an energy storing and returning composite prosthetic foot during amputee running is considered. It is shown that the rig can simulate the running action of an amputee runner and return similar ground contact time. It has also been shown that if a small input force is applied in a timed and sympathetic manner to the prosthetic spring-mass system the amplitude of oscillation increases which agrees with results of previous research. The rig will allow the design variables that contribute to the response of a prosthetic foot during running to be understood and optimised to possible improve the foot's performance.