The Food and Drug Administration (FDA) has approved the Patient Specific Talus Spacer (Additive Orthopaedics) for humanitarian use in the treatment of avascular necrosis (AVN) of the ankle joint.

The Patient Specific Talus Spacer is a first-of-its-kind 3D-printed implant for talus replacement individually designed for each patient using computed tomography (CT) imaging. The approval is supported by data from 31 patients and 32 talus replacement surgeries; 1 patient had operations on both ankles. 

Results showed that average reported pain decreased from “moderate to severe” to “mild” 3 years after the surgery. Moreover, an improvement in the average range of motion in the ankle joint was observed. Pain and functionality were assessed using standard subjective scoring systems.

The most common adverse events reported were pain and scar tissue at the surgery site. Three of the 32 cases required additional surgeries at the 3-year mark.

“Avascular necrosis of the ankle, while a rare condition, is a serious and potentially debilitating one that causes pain and can lead to inhibited motion of the ankle joint, and in some cases, removal of part of the leg,” said Capt. Raquel Peat, PhD, MPH, USPHS, director of the FDA’s Center for Devices and Radiological Health’s Office of Orthopedic Devices. “Today’s action provides patients with a treatment option that could potentially reduce pain, retain range of motion of their joint and improve quality of life.”

The FDA reviewed the Patient Specific Talus Spacer through the humanitarian device exemption process. A Humanitarian Use Device is a device that is intended to benefit patients by treating or diagnosing a disease or condition that affects not more than 8000 individuals in the United States (US) per year.

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  1. FDA approves first in the world, first-of-its-kind implant for the treatment of rare bone disease as a humanitarian use device. [press release]. Silver Spring, MD: US Food and Drug Administration; February 17, 2021. 
  2. Additive Orthopaedics® announces FDA approval of Patient Specific Talus Spacer, first approved in the U.S. [press release]. Little Silver, NJ: Additive Orthopaedics, LLC; February 17, 2021.