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.