For the first time ever in Spain, surgery to implant a prosthesis (which has been produced with a 3D printer and is exactly identical to the patient's knee to enable them to recover their mobility) will be carried on 10 September at the Hospital Ochoa in Marbella.

Traumatology specialist Ignatius Chatziandreou will perform the operation using a technique first used 12 years ago in the USA and six years ago in Europe, with implants produced by ConforMIS, a multinational company specialising in medical technology and with whom Dr Chatziandreou collaborates.

The individual character and design of the implant means the prosthesis "adjusts precisely to the exact anatomy of the patient and therefore prevents many problems regarding discomfort, pain or unnatural movements," say sources at the Hospital Ochoa. In fact, these personalised prostheses have the advantage, for those who usually use them, of "adapting better to the structure of the knee".

They are especially recommended for patients with severe osteoarthritis, and there are two types: lateral or total. The average age of patients who need a knee prosthesis is around 60, although in some cases it can be as young as 40.

The only people for whom this operation is not suitable are those with an allergy to steel, chrome or cobalt (as these are used to make the implant), or anyone whose collateral ligaments are affected.

The operation is carried out under general anaesthetic or epidural, depending on each case, and takes approximately one hour. Recovery takes about four weeks and the patient only has to spend a few days in hospital. Many begin to walk from the first day.

The ConforMIS company "produces a precisely designed prosthesis, working from scans of the patient's knee; the joint is completely made-to-measure and will adapt totally to the shape of the leg," say the hospital sources.

The automised design process "perfectly matches the size and shape of the knee in 3D. Once the model has been created, a wax mould is printed in 3D and that is used to shape the femoral and tibial components of each implant. ConforMIS also prints all the disposable instruments, specific to each patient," they explain.

Dr Chatziandreou joined the Hospital Clínica Ochoa in Marbella last year and he is the head of the surgical team which will be carrying out these implants. He performed over 1,000 operations of this type between 2002 and 2015, while he was working in Dortmund (Germany).