Ideation Phase - November 4th
Idea #1 Modular Cementless Implant
- Will have a tri-tapered shape so it is smaller allowing more bone preservation.
- Cementless implants are less invasive and allow bone growth.
Idea #2: Partially Hollow Implant
- Porous implants with holes will allow for bone growth inside creating a stronger fit.
- Porous materials allow for coatings to stick on longer.
Idea #3: Drug Delivery System
- Channels along the implant will allow for medication to flow throughout the entire implant.
- Improved recovery time.
Initial idea - November 12th
The initial plan involves a drug delivery system, modular acetabular cup, and tri-tapered design.
- This design incorporates many of the ideas presented by everyone. It took the pros of everyone and combined them to create an initial design.
- Since Perthes disease had worn down the pelvis heavily, a bone graft is needed which is why the drug delivery system is used to prevent infection.
- The modular cup allows for a large range of motion and allows for more flexibility for the patient.
- The tapered design allows for an easier fit into the femur and decreases the risk of implant fracture.
Reflection and Skills
Materials Identification - November 18th
| Material |
Structure ⚛️ |
Properties 🧪 |
Processing ⚙️ |
| Carbon Fiber Polyether Ether Ketone (CFR-PEEK) ⭐ |
Polymer and covalent bonded |
Chemically inert and low wear rate |
Can be 3D printed to change porosity levels and elastic modulus 1 |
| Ti Metalic Glass |
Metal alloy and metallic bonding |
Similar EM of bone and good corrosion resistance |
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| Tantalum |
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Very resistant to wear and high biocompatibility |
Porous tantalum is good for drug delivery as it has antibacterial functions |
Carbon fiber-reinforced polyether ether ketone was chosen as the material for the femoral stem due to its ability to be bioinert in the body and its processing procedure. Allowing the material to be printed with different porosity and elastic modulus allows the patient to have a custom-tailored implant suiting their needs.
💡 What would happen if we chose a different idea?
Modifications to Design - Nov. 24th to Dec. 1st
November 24th: second iteration
- Included dimensions to fit the patient's needs and size.
- Determined hole size for water flow.
November 29th: Final Sketch
- All edges should be rounded to reduce crack propagation.
November 25th: Third iteration
- Canals for drug delivery will be offset to increase stability.
- Holes will be 10mm apart.
December 1st: CAD Model Prototype
- The stem is tapered to the bottom to fit the narrowing regions of the femur.
Reflection and Skills
Final CAD Model - December 3rd
This is the final design of the hip implant with the acetabular cup, liner, and femoral stem.
- This dual-tapered design contains channels that allow for effective drug delivery.
- I was in charge of the femoral stem while my partner helped create the acetabular cup, liner, and screw. This required constant communication as we had to ensure our parts fit well with each other.
- The approach I took to make this revolved around creating the stem using rectangles and then shaving it down afterward. However, the more efficient approach would have been to draw the stem first and then extrude it outwards making it a simpler process.