An 84-year-old man in China is the first recipient of a knee replacement using 3D printing technology to fill large bone defects with tantalum, a rare metal. The hospital, First Hospital Affiliated to Southwest Hospital, is located in Chongqing Municipality.
Knee replacement surgery is a common solution for people with severe, chronic knee pain. It’s an effective way to treat late-stage knee disease, reducing pain and increasing quality of life for patients. Traditionally, knee-replacement procedures have generally used cement implants or bone grafts, both of which can cause problems that affect the implant’s lifespan and stability. The shape of bone defects varies considerably, and modular metal cannot correct the defects, but porous tantalum solves that technical challenge.
The 3D printed tantalum implant is more compact and stable than a titanium implant would have been, factors that simplified the surgical procedure and lowered the risk of complication. The surgical team built a porous 3D model, tailored for the patient’s particular knee problem using visual data from CT scans. Using the information from the scan, the defective knee was digitally reconstructed prior to virtually simulating the implantation procedure.
In the past, the high melting point of tantalum (3,020 degrees C) would disqualify it from use in metal 3D printers. However, Southwest Hospital used specialist equipment to 3D print the patient’s knee implant in the tantalum.
The shape of the bone defects varies greatly, and existing modular metal cannot correct the defects. Porous tantalum has been developed to solve the technical problem. Tantalum pads are individually designed for patients by computer-aided design and precise 3D-printing technology.