FDA has approved a 3D-printed medical device for humanitarian use in the treatment of the rare bone disease avascular necrosis (AVN).
Additive Orthopaedics makes the device, the Patient Specific Talus Spacer, by using CT image data to inform 3D printing. The ankle implant is designed to enable patients to retain motion and reduce pain.
- FDA approved the implant on the strength of data from 32 surgeries. Additive Orthopaedics plans to start marketing and selling the device immediately.
AVN is currently treated by fusing the joints in the foot and ankle or amputating below the knee. Both approaches alleviate the pain associated with AVN, a condition characterized by the death of bone tissue and deterioration of the cartilage that stops bones from rubbing together. However, the existing options also affect mobility, either by eliminating joint motion or removing the foot entirely.
Additive Orthopaedics is pitching its spacers as a way to alleviate pain and retain joint motion. The spacers are designed to replace the talus, an ankle bone that can collapse in patients with AVN. By basing the implants on CT scans, Additive Orthopaedics can tailor the devices to the anatomy of each patient. The company makes the 3D-printed implants from cobalt chromium alloy.
FDA authorized the implant after reviewing data from 32 surgical procedures. Three years after the procedures, patients typically described their pain as mild, down from moderate to severe before the treatment. The range of motion in the ankle joint improved as well.
Surgeons performed three additional surgeries on the patients over the course of the three-year trial. FDA and Additive Orthopaedics said recipients of the implants may need to undergo fusion at a later date if their condition deteriorates despite treatment with the 3D-printed devices. However, the implant will enable patients to retain motion while suffering less pain until fusion is required.
FDA cleared the implant for use via its humanitarian device exemption process. The implant was eligible for the exemption as it is used in the treatment of a condition that affects fewer than 8,000 people a year in the U.S.
Additive Orthopaedics plans to start marketing and commercializing the medical device immediately. The talus implant joins a portfolio of 3D-printed medical devices designed to address a range of foot and ankle conditions.
In 2017, FDA issued guidance it called its initial thinking on 3D printing of medical devices, as part of a broad category called additive manufacturing. Big players like Medtronic have made forays into the space.