Reducing design time of scoliosis brace by 59%
Semi-automated workflow for designing custom orthopaedic braces for idiopathic scoliosis with Geomagic Freeform saves 21 minutes per brace.
Featured partner: Teoresi Group
Orthopaedic braces are a common treatment for patients suffering from idiopathic scoliosis used to prevent further progression of the issue. These devices must be designed to highly specific requirements and customised to comfortably fit the patient’s body.
A digital workflow offers several benefits. It enables orthotists to create a record of the process, analyse and improve it. They can design complex patterns of holes for greater breathability, comfort and visual appeal. The result is a brace the patient wants to wear longer, improving the outcome of the treatment.
While in traditional clinical practice orthotists make braces manually, today many use digital methods based on 3D scanning and 3D design software.
The next frontier is standardisation and automation. As models are built digitally, it’s easier to keep track of successful models and use them to define best practices. Moving the design into software has also enabled automation and additional time savings.
A significant step in this direction was made in a research project from the Polytechnic University Turin. Master’s student Giulia Cairo developed a semi-automated digital workflow for designing custom orthopaedic braces for patients with idiopathic scoliosis using Geomagic Freeform.
“The workflow can effectively guide orthotists throughout the 3D modelling process, which is often complex for professionals with limited CAD experience. At the same time, experienced users can benefit from a significant reduction in design time,” Cairo says.
“It achieved a 59% reduction in overall processing time, while approximately 71% of the workflow was shown to be fully or partially automated, leading to a considerable decrease in manual workload,” she adds.
Geomagic Freeform integrates with haptic devices which allows user to physically feel a digital model.
Teoresi Group, a Geomagic software partner, supported the project by providing engineering know-how, technical tutoring and dedicated workspaces for the research activities. Under the guidance of Andrea Orlando, Products and Solutions Engineer at Teoresi, Geomagic Freeform was used together with other technologies to build a complete digital workflow from scan data to brace modelling. This contribution helped translate the research objectives into a practical, reproducible process.
Limitations of conventional methods
The traditional approach to making braces involves plaster casting, and the quality of the result depends on the experience and know-how of the person fabricating.
An orthotist makes a cast to obtain a negative mould of a torso. They create a positive model of the body by filling the negative with liquid plaster and then remove or add material to areas of thrust, relief, or expansion.
Finally, the brace is made by thermoforming plastic materials onto the positive. The final brace is fitted with fasteners and padding and subsequently adapted to the patient during one or more fitting sessions.
While this tried-and-tested method produces good results, it comes with several drawbacks. For the technician and orthotist, the process is very labour-intensive and time-consuming, increasing the overall cost of production.
Poor reproducibility is another limitation. Because the process is manual, it’s difficult to keep track of the modifications. Nor is it easy to archive the casts as they take up physical space and deteriorate over time. All of this makes standardisation difficult.
Digital design of braces
Digital tools solve these challenges. A CPO scans the torso, imports the 3D scan data into Geomagic Freeform, and creates a model of the brace. The brace can be manufactured by thermoforming on top of a physical model of the torso or by 3D printing.
In a digital approach, manual operations typically performed on the physical prototype are transferred to the software, including any modifications. The benefit is that changes are measurable, repeatable, and comparable - all of which goes into standardising the process.
3D modelling an orthopaedic brace in Geomagic Freeform
Furthermore, the ability to save and revise subsequent versions of the design facilitates the optimisation of the brace and the monitoring of changes over time.
Feel the difference with Geomagic Freeform
Designing handcrafted-style sculptural forms, such as braces, would be difficult or impossible in typical CAD software. Instead, Cairo chose Geomagic Freeform for the project.
“Geomagic Freeform is a highly effective organic modelling software, particularly for applications that require precise customisation of anatomical geometries. One of its main strengths is the ability to carefully model specific regions of interest while maintaining a very intuitive interaction with complex organic shapes,” she says.
The software’s integration with touch-based design devices is another important advantage. This is particularly helpful for technicians, who are used to shaping materials with hands. Haptic devices allow them to physically ‘feel’ and manipulate the digital model.
Automating design with Dynabots
The key contribution of Cairo’s research – standardisation and automation of brace design – was achieved with Dynabots. Cairo configured the tool to reproduce operations for processing scan data and designing the brace. This allowed her to define a standard procedure other users can apply.
Additionally, the Dynabot simplifies the design process. O&P technicians are not software experts and would require software training. Cairo’s workflow pares down the operations they need to perform inside the software, enabling them to quickly become productive.
Expert in the driver’s seat
Cairo organised the design into well-defined steps, 71% of which are semi-automated or automated. This reduces the variability associated with purely executional phases but leaves the technician in control of decisions that have the greatest clinical impact.
Automating the process 100% wasn’t the objective. The design of a brace for scoliosis depends heavily on the patient’s morphology, the type of curve, and the corrective strategy adopted by the technician. “An excessive level of automation could be limiting, reducing the ability to adapt the device to specific clinical needs,” she says.
Instead of full automation, she struck a balance between technical standardisation and design freedom. As a result, the time spent on design is 21 minutes shorter than without automation. The additional time could be used on analysis of the biomechanics of the spine or ensuring geometric consistency and fit.
The semi-automated workflow has been tested by CPO Luca Gualerzi, who identified reproducibility as its key advantage. “We need to spread the use of digital technology. If we develop best practices principles and simplify the interface, more technicians will be interested in this approach,” he says.
New era for digital workflows in O&P
For technicians and CPOs, the workflow opens the doors to higher efficiency, lower workloads and faster production.
“The proposed method makes it possible to considerably speed up the development process and potentially produce nearly twice the number of devices within the same timeframe compared to more traditional CAD approaches,” Cairo says.
Most importantly, the reduction in manual work allows orthotists to devote more time to patient care. “Patient interaction remains essential to ensuring that the final orthosis is not only biomechanically effective, but also comfortable and wearable for prolonged daily use, which is a key factor in therapeutic success,” she concludes.