Scientists are turning to artificial intelligence to create advanced materials that mimic human bone, a breakthrough that could significantly improve hip replacements, fracture healing and the future of orthopedic medicine.
Researchers say these AI-designed materials, known as metamaterials, could help develop stronger, longer-lasting implants that better integrate with the human body while reducing the need for repeat surgeries.
Hip replacement procedures are among the most common orthopedic operations worldwide. However, artificial joints are exposed to enormous stress over time, with patients taking nearly two million steps each year. This constant pressure gradually wears implants down, often requiring replacement surgeries after a decade or more.
To address this challenge, researchers are attempting to replicate the complex structure and behaviour of natural bone using artificial intelligence and advanced engineering.
Amir Zadpoor and his team at Leiden University Medical Center in the Netherlands have been developing a new class of materials capable of behaving in unusual ways under pressure.
The researchers were searching for a material that becomes thicker when stretched instead of thinning — a rare property found in so-called “auxetic materials.” Such materials could help implants remain firmly attached to bone while absorbing stress more effectively.
Traditional auxetic materials, however, are usually too soft for medical implants. To overcome this limitation, the team used artificial intelligence to identify microscopic material structures that could combine stiffness, durability and flexibility.
Using machine learning models, the researchers designed a metamaterial with properties that closely resemble human bone. Metamaterials are engineered substances whose internal structures can be manipulated to create unusual mechanical behaviours not commonly found in nature.
Scientists say artificial intelligence dramatically speeds up the discovery process by allowing researchers to test thousands or even millions of possible material structures in a short period of time.
Experts believe such technology could revolutionize orthopedic medicine.
At TU Delft, researchers are also developing AI-generated materials aimed at improving fracture healing, particularly among elderly patients.
Current fracture treatments often rely on metal implants such as titanium plates and screws. While effective for stability, these implants are much stiffer than natural bone, sometimes preventing healthy stress distribution needed for proper healing.
Researchers are now experimenting with softer, porous metamaterials that imitate the structure of trabecular bone — the honeycomb-like internal tissue found at the ends of long bones.
Sid Kumar and his colleagues used machine learning to generate “spinodoid” structures that closely match the shape, strength and flexibility of human bone.
The resulting designs can be produced using 3D printing and may eventually allow implants to encourage natural tissue growth while adapting to different areas of the body.
According to researchers, future implants could even be customized for individual patients using AI-powered design systems tailored to specific anatomy and movement patterns.
Mohammad Mirzaali said different parts of an implant may require varying levels of stiffness and porosity depending on how tissue grows and how force is distributed across the bone.
Scientists say the combination of artificial intelligence, biomaterials and 3D printing is opening entirely new possibilities in medical engineering.
Although many of the technologies are still being tested, researchers believe AI-designed bone implants could eventually improve patient recovery, reduce implant failures and extend the lifespan of orthopedic replacements worldwide.
