From Clinical Need to a Personalised Medical Solution in 24 Hours

How collaboration and rapid fabrication solved a case where off-the-shelf orthopaedic options fell short

Image 1: Final product in action

Every so often, a case I see at hospital clearly highlights the gap between what is clinically needed and what is commercially available within the required timeframe.

A young footballer presented in the hospital following a distal radio-ulnar fracture. The plaster cast had just been removed, and the treating physician was open to a return to sport, but with one important condition: additional protection for the forearm.

At first glance, this appeared to be a straightforward case. Wrist braces are widely available and commonly used in similar scenarios. However, once we reviewed the options in detail, a clear limitation emerged.

None of the available braces extended far enough along the forearm to provide the level of protection required.

This left us with a familiar but important challenge: how do you provide something clinically appropriate when standard solutions fall short?

A Collaborative Approach

Rather than trying to adapt an off-the-shelf solution beyond its intended use, I brought the case to my husband, who is an engineer and leads the product development in my team.

What I understood clinically, and what he understood from a design and materials perspective, came together quickly into a practical solution.

The requirements were clear:

• extend protection further along the forearm

• maintain comfort and wearability

• allow removability for hygiene and inspection

• deliver rapidly - ideally within 24 hours

Time was a critical factor. The patient was seen on a Friday and keen to return to football by Monday. Any delay would significantly reduce the practical value of the solution.

After a focused discussion that same evening, we decided to develop a bespoke, thermoformable splint using a combination of 3D printing and manual forming.

This was not about creating a new product, but about solving a specific clinical problem for a specific patient, as efficiently and safely as possible.

We were initially mindful of regulatory considerations, particularly around CE marking. However, this case fell within the definition of a custom-made medical device under EU Medical Device Regulation (MDR 2017/745). The splint was fabricated for a single named patient, based on a clinician’s request and specific clinical need, and was not mass-produced or placed on the market. This is analogous to plaster casts and bespoke orthotic devices routinely fabricated in clinical settings without CE marking.

Design and File Selection

To accelerate the process, we sourced a base STL file from an open-access repository and adapted it to suit the case.

Rather than designing from scratch, this allowed us to reduce design time, leverage an already functional geometry, and focus on fit and application rather than initial modelling.

The key design features included:

• extended forearm length beyond standard wrist braces

• thumb relief opening

• perforation pattern for ventilation and weight reduction

• integrated strap holes for Velcro fixation

• uniform thickness of 4 mm for structural integrity

Fabrication and Forming Process

The splint was 3D printed flat in PETG, a material chosen for its ductility during heating, resistance to cracking after forming, and suitability for repeated adjustment. Printing flat ensured a predictable and efficient fabrication process. The print was completed overnight (approximately 2 hours of print time), ready for fitting the following morning.

Images 2 & 3 - 3D printed plate; Printed plate being prepared for hot water immersion.

Prior to forming, the forearm was protected using multiple layers of bandaging and polyester padding to provide thermal insulation and improve comfort. Shaping was carried out in two stages.

Stage 1 – Global forming:The plate was softened in hot water to establish the overall geometry, including the forearm curvature, wrist position, and thumb alignment. This stage enabled rapid formation of the general shape, although the material cooled quickly, limiting fine adjustments. The patient’s arm was not used in this step.

Stage 2 – Local refinement:To improve the fit, a standard hair dryer was used to selectively reheat specific regions of the splint. Importantly, the splint was removed from the patient prior to each heating step, ensuring no direct heat exposure to the skin. This allowed controlled, incremental adjustments to relieve pressure points, refine edges, and improve conformity.

Care was taken throughout to maintain the wrist in a neutral position and to avoid applying pressure over the fracture site.

This second stage proved critical, providing the time and control needed to achieve a comfortable and well-fitted result.

The Final Outcome

Image 4: fitted custom brace superior view

Image 5: fitted custom brace inferior view

Images 4 - 6 - fitting of final product; 3D printed splint in action.

The final splint extended further along the forearm than standard braces, providing the additional protection required while remaining lightweight, removable, and ventilated.

It allowed the patient to return to football activity in line with the physician’s guidance, offering both protection and practicality.

The device can also be reheated and adjusted if needed in the future, allowing for minor refinements over time.

Conclusion

This case was not about replacing existing orthopaedic solutions, but about addressing a clinical need that sat just outside what was readily available.

Digital fabrication allowed us to move from problem to solution within 24 hours, delivering a patient-specific outcome where standard options fell short.

More broadly, it highlights an important opportunity: when clinicians and engineers collaborate closely, even small but time-sensitive gaps in care can be addressed quickly, safely, and effectively.

Anna Maria