Chinese hospital implants additively manufactured tantalum knee joint
November 30, 2017

An AM tantalum implant was used to fill defects in an 84 year old man’s knee (Courtesy China Global Television Network)
A hospital in Chongqing municipality, China, has become what is believed to be the first in the world to perform a ‘knee revision’ surgery using a metal additively manufactured joint, reports China Global Television Network. In the surgery, an eighty-four year old man with severe arthritis had large sections of the bones in his knee replaced with tantalum implants.
With the incidence of arthritis among people aged 50-59 now at 62%, the hospital stated that it performs roughly four-hundred knee replacement surgeries annually. However, in conventional knee replacement surgery, bone defects can occur around the joint due to post-operative infections.
In addition, the shape of bone defects varies greatly from person to person; using ‘off-the-shelf’ implants, surgeons are required to take time during the surgery to shape the implant to match the patient. As a result, hospitals have for some time recognised the potential of additively manufactured knee replacements – which allow implants to be custom-shaped to the recipient – with polymer versions having been implanted successfully in the past.

According to hospital surgeons, the patient regained mobility a day after receiving the tantalum implant (Courtesy China Global Television Network)
This marks the first knee replacement surgery using a joint produced by metal AM. Tantalum is typically used in dental and surgical implants; for this implant, porous tantalum was used, to allow future bone in-growth.
According to the hospital surgeons, the patient regained mobility a day after receiving the tantalum implant and was expected to be discharged from the hospital in just four to five days.