Encouraging news for hip surgeries: New hip prosthesis lasts over 20 years

December 3, 2012
Encouraging news for hip surgeries

A team of researchers at the University Department of Orthopaedics at the MedUni Vienna / Vienna General Hospital has for the first time investigated the durability of Zweymüller hip prostheses, which were developed at the end of the 1970s, over a period of 20 years. The result: the stem of the endoprosthesis, which was named after the Professor of Orthopaedics at the Vienna General Hospital and developed over 30 years ago, lasts for at least 20 years. "This shows that the fear over hip prostheses is unfounded. It is better to live with a prosthesis and without pain than to live without one and be in pain," says Reinhard Windhager, Head of Orthopaedics at the MedUni Vienna / Vienna General Hospital.

The Zweymüller , developed at the end of the 1970s, was one of the first to be anchored in the bone without using to fix it in place. The prosthesis's special geometry and surface guarantee its stable anchoring and natural integration into the bone. Its hallmark feature is the roughened surface of the stem, which provides a place for the new to grow onto.

In the past, the endoprosthesis has been made from ultra-lightweight titanium, has been implanted millions of times over, and has even been used in minimally with an in the skin measuring around ten centimetres. Nowadays, it is used in combination with a ball and socket made from ceramic, which produces less wear. In 67 per cent of the 200 investigated, the durability of the ball and socket, i.e. the second outcome of the study, which has now been published in the highly respected journal The , is still intact after 20 years.

Around 300 total hip replacements are carried out at the University Department of at the MedUni Vienna / Vienna General Hospital every year, half of them involving Zweymüller prostheses. Patients are even able to carry out sports without impacting on the durability of the prosthesis or causing it to loosen any sooner. Patients are becoming younger and younger – particularly in light of the prosthesis's excellent quality. In the past, says Windhager, the average age of patients receiving hip replacements was significantly higher than 65 years, but nowadays it continues to fall below this.

Research into even better integration of prostheses

The Department of Orthopaedic Surgery at the MedUni Vienna is also carrying out research into the development of new, even better prostheses using the so-called radiostereometric analysis (RSA). Says Windhager: "The movement of the implant relative to the bone is measured in three dimensions. We are able, as it were, to watch the implant while it moves. We achieve accuracies of up to 0.1 millimetres." Within the first two years after the operation, this means that it is possible to obtain an early diagnosis of how the implant is integrating into the bone and of its . RSA also allows new materials that are used for the new types of prosthesis - including of the knee, foot or spine - to be compared with each other.

"RSA is the ideal tool for the development of new products in orthopaedic surgery. Our aim is to further improve the integration of the implant into the bone. The biology is especially important here; we're able to see what's happening around the prosthesis," says the Head of Department.

Explore further: Patients at risk of knee joint complications when new technology is used

More information: Kolb, A. et al., Cementless Total Hip Arthroplasty with the Rectangular Titanium Zweymüller Stem, J Bone Joint Surg Am. 2012;94:1681-4. dx.doi.org/10.2106/JBJS.K.01574

Related Stories

Hip implant for long-term use

May 4, 2012

Hip replacement is one of the most frequent operations carried out in Germany. Each year, doctors implant some 200,000 artificial hip joints. Often the artificial hips need to be replaced just ten years later. In the future, ...

Recommended for you

A recipe for long-lasting livers

April 22, 2015

People waiting for organ transplants may soon have higher hopes of getting the help that they need in time. Researchers at the RIKEN Center for Developmental Biology have developed a new technique that extends the time that ...

Surgeon to offer ideas on a way to do human head transplants

February 26, 2015

Sergio Canavero of the Turin Advanced Neuromodulation Group has made it known that he intends to announce at this summer's American Academy of Neurological and Orthopedic Surgeons meeting, that he believes he has put together ...

New tool helps guide brain cancer surgery

July 3, 2014

A tool to help brain surgeons test and more precisely remove cancerous tissue was successfully used during surgery, according to a Purdue University and Brigham and Women's Hospital study.

New imaging technique sharpens surgeons' vision

February 11, 2014

Which superhuman power would you choose for help on the job? For Dr. Julie Margenthaler, it's a technology that brings to mind X-ray vision, used for the first time Monday during an operation to remove a patient's lymph node.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.