Bringing Together CAD and Image Data with Simpleware Design Link

Simpleware Design Link is particularly powerful when designing patient-specific implants and devices. One key example of this capability is in designing a primary total hip replacement implant. 

How it Works – Example: Hip Implant Design and Placement

1. Segment Your Image Data in Simpleware ScanIP

A CT scan of the patient’s pelvic region can be imported quickly and simply into Simpleware ScanIP to generate a model of the patient’s anatomy.

A wide range of segmentation tools is available to create a model of the bones in the pelvic region. Fully automated AI solutions generate a segmented model with key landmarks in only a few minutes with a single click. Semi-automated segmentation tools include interactive threshold, flood fill, and the split tool. These can both be combined with our range of Simpleware image filters and 3D editing tools, ideal for overcoming problems caused by artifacts in the image data. For more information on our range of segmentation tools for Orthopedics, please read our blog Top Tips to Speed up Orthopedic Image Segmentation.

2. Place Landmarks in Simpleware Software

Once a clean and accurate model of the patient anatomy has been created, landmarks can be generated (using Simpleware AS Ortho or the measurement tools). These key features of the bone structure influence the implant design and can be used as-is or modified to suit. These landmarks can also be combined with key measurements such as:

• Diameter of the femoral head
• Femoral neck width and length
• Position of the femoral neck axis
• Angle between the neck of the femur and the shaft
• Position of the femoral-shaft axis
• Width of the femoral shaft

3. Design in SOLIDWORKS and Import with Simpleware Design Link

In SOLIDWORKS, you can choose your most appropriate CAD implant assembly to work with. The implants designed in SOLIDWORKS are then imported into Simpleware ScanIP using Simpleware Design Link. The CAD implant can also be registered to the Simpleware model over the joint that is to be replaced using either landmark registration techniques or through manual manipulation, or a combination of both. The position can be accurately checked in the 2D slice views and the 3D view to ensuring a good fit.

Once the CAD implant is in the correct position, adjustments can be made to the part to make it more suitable for the specific patient. You can change the:

• Size of the acetabular shell
• Thickness of the liner
• Angle of the neck of the implant
• Length or diameter of the stem
• And much more

Measurements perforated in Simpleware ScanIP can inform these decisions, so the implant resembles a healthy joint with a similar freedom of movement. All these changes to the implant can be made directly to the parameterized assembly in SOLIDWORKS and the changes can be synced by pulling the geometry back into Simpleware ScanIP.

Key Benefits of Design Link

• Speed up designs of customized parts and devices
• Generate accurate models in both CAD and image space
• No manual import/export – just sync designs
• Reduce data management overheads

Applications: Orthopedics, Maxillofacial, Cardio, and More…

• Personalized implant design
• Patient-specific cutting guides
• Customized implantable devices
• Anatomy-specific designs for trauma or deformities

What Next? Using Models for Design and Simulation

Once you are happy with the design of the implant or device, you can generate a model of the anatomy and the implant together. You might want to export surface meshes for 3D printing, or create volume meshes to simulate the performance of the implant.

Simulation through finite element analysis would allow you to see the performance of the device when placed in the patient’s anatomy. Volume meshes generated in Simpleware FE can also include information on the material properties of a patient’s bones by using greyscale material mapping to include density, Young’s modulus or Poisson’s ratio from a calibrated CT scan. You could similarly try a range of implant designs and/or positions to test the fit and function of the implant. This could also help to indicate the likely lifespan of the implant.

All this information allows you to design a tailor-made implant for the patient and understand patient outcomes ahead of surgery to make more informed decisions.

Simpleware Design Link can also be used for more detailed design work. For example, where there has been trauma or deformities to the patient anatomy, and standard implants cannot be tailored to fit. In these cases, new parts need to be designed from scratch or significantly altered to have larger plates or extra fixings based on the patient’s individual needs. Simpleware surfaces can be pushed with landmarks and measurements directly into an existing SOLIDWORKS assembly as reference geometries. Using this approach, you can generate tailored solutions based on an accurate model of the patient’s unique anatomy.

Learn More

Attend our Live Presentation and Demo on October 21, 2020, or watch on-demand after the live session.