Orthopaedic surgery to benefit from stem cell-powered implant

The University of Glagow is collaborating with Glasgow’s Southern General Hospital to develop a new type of orthopaedic implant which could be considerably stronger than the current generation of products.

Currently, implants are commonly made from materials such as polyethylene, stainless steel, titanium or ceramic and have a limited lifespan due to loosening, requiring replacement after 15 or 20 years of use.

In hip replacement surgery, the head of the thigh bone is removed and replaced with an implant which is held in place by a rod fixed inside the marrow along the length of the bone.

Marrow is a rich source of mesenchymal stem cells, which have the potential to divide, or ’differentiate’, into other types of cells such as skin, muscle or bone which can improve the process of healing. However, stem cells can also differentiate into cells which have no use in therapy.

Artificially controlling the final outcome to ensure the desired type of cells are created is very difficult, even under laboratory conditions.

When traditional implants are fixed into bone marrow, the marrow’s stem cells do not receive messages from the body to differentiate into bone cells, which would help create a stronger bond between the implant and the bone.

Instead, they usually differentiate into a buildup of soft tissue which, combined with the natural loss of bone density which occurs as people age, can weaken the bond between the implant and the body.

The team from the University of Glasgow’s Colleges of Science and Engineering and Medical, Veterinary and Life Sciences have found a reliable method to encourage bone cell growth around a new type of implant.

The implant will be made of an advanced implantable polymer known as PEEK-OPTIMA, from Invibio Biomaterial Solutions, which is already commonly used in spinal and other orthopaedic procedures.