Capstone/Senior Design - The WRISTraint:
a Scapholunate Ligament Surgery Implant

This project placed 3rd in the Georgia Tech BME Capstone Expo, Fall 2022

Scapholunate ligament repair/reconstruction surgeries have a very high failure rate, ranging from 40-70%. The challenge in this space is that the bones around the ligament need to remain still for 6-8 weeks following the surgery, but immobilizing the wrist in place for that amount of time can result in permanent loss of motion.

I worked with a team of biomedical engineering students to interview primary users such as surgeons and physical therapists to understand the problem space and identify key needs. We designed and modeled prototypes and proofs of concepts made of plastic, wood, aluminum, and titanium using 3D printers, laser cutters, and waterjets in the school machine shops. We simulated durability tests on SolidWorks and verified them using physical tensile and torque testers. We borrowed a Micro-C X-Ray from OXOS Medical, using it to validate our final proof of concept via cadaveric testing.

Our final device, The WRISTraint, was a small titanium implant that stablized only the necessary bones will still allowing for general wrist movement. Cadaveric testing showed that this implant is compatable with current industry processes, and successfully fixed the bones in place without immobilizing the whole wrist. Physical verification showed that the WRISTraint can resist nearly double the necessary pulling and twisting forces.