As per the notification on 17 February 2021, the United States Food and Drug Administration (US-FDA) granted its approval to the Patient Specific Talus Spacer implant for humanitarian usage. This is the first-of-its-kind implant to successfully replace the talus (bone in ankle joint connecting foot and leg) for managing patients with avascular necrosis of the ankle joint.

This implant offers a joint-sparing alternate to other surgical interventions frequently utilized in late-stage avascular necrosis. This rare, progressive, debilitating, and serious condition leads to the death of the bone tissue stemming from a lack of blood supply to the bone tissue, causing it to become necrotic.

It leads to severe pain, considerably disable motion of the ankle joint, and in few cases, may cause the removal of part of the leg. Late-stage avascular necrosis of the ankle may cause a partial or full collapse of the talus bone. The Patient Specific Talus Spacer yields a therapeutic choice to alleviate pain, improve the patient's quality of life and retain the range of motion of the affected joint.

This 3D-printed implant is modeled from computed tomography imaging and can be satisfactorily utilized in talus replacement operation. It is developed for each subject individually and is fitted to the patient’s specific anatomy. During the replacement operation, the removed talus bone is replaced with the cobalt-chromium alloy implant. The talus replacement surgery with the aid of the Talus Spacer implant is intended to be a joint-sparing approach, as it permits the patient to retain motion in the ankle joint.

The FDA reviewed the implant's data with the aid of the humanitarian device exemption (HDE) process. The data favoring the probable advantage and the safety of this promising implant incorporated outcomes from 31 participants and 32 talus replacement operations (one individual had surgeries on both ankles) with the aid of the implant. At three years after surgery, the average reported pain declined from “moderate to severe” before surgery to “mild” after surgery.

Also, the average range of motion in the ankle joint improved. These outcomes were examined utilizing the standard subjective scoring systems for functionality and pain. By the three-year mark, out of 32 cases, three extra surgeries were reported. Scar tissue and pain at the operation site were the most commonly noted side effects.