© surgebright

Making Surgical Screws From Bones

ArticlePress release
Bone, Muscle, & Joint
Surgical Procedures
+1
Contributed byMaulik P. Purohit MD MPHOct 02, 2017

Biomechanics from TU Graz, are developing surgical screws from donated human bone material for foot and jaw surgery together with surgebright, a start-up from Linz, Austria.

To heal broken bones using medical help, the surgical method of choice for decades have been metal screws, mainly made of titanium or stainless steel. During and after the healing process, these metal screws are seen by the body as disturbing foreign bodies and often have to be removed in a further unpleasant surgical intervention.

Together with TU Graz's Institute of Biomechanics, in 2013 orthopaedist Klaus Pastl developed an alternative in orthopaedics and accident surgery: the "Shark Screw," made of the specially compact and hard middle layer of the human thigh bone (femur). So what exactly are the advantages of screws made of donated bone material? The metal doesn't have to be removed and a second operation -- as unpleasant as it is risky and expensive -- doesn't have to be carried out because the donated material has completely healed into the bones. So well healed that the transplant is no longer visible in an x-ray after one year. On top of this, the body recognises the bone screws as belonging to its own body, and danger of infection and complications is reduced to a minimum. The Shark Screw is being produced from the start-up surgebright, which was founded in 2016, in cooperation with the German Institute for Tissue and Cell Replacement (DIZG) in Berlin. The patented technology is already being used in 14 Austrian hospitals.

Further development for foot and jaw surgery

Just as before, surgebright works closely together with the Institute of Biomechanics at TU Graz. Together, they are developing new prototypes of bone screws for foot and jaw surgery in the FFG (Austrian Research Promotion Agency) funded project Bonescrews.

Gerhard Sommer, from the Institute of Biomechanics at TU Graz, explains: "We have to completely rethink the bone screw for application in foot and jaw surgery, and want to develop prototypes for both applications in the framework of the project. In maxillary surgery, extremely small screws are necessary, approximately 20 mm long, which have to withstand great stresses. Because relative to size, the jaw muscle is the most powerful muscle in the human body. In foot surgery, although the screws are bigger, between four and six centimetres long, they are also exposed to large forces, for instance bending forces in surgical corrections on the tarsus."

Complex biomechanical tests

The design of the thread of the screws alone has an enormous effect on the bending and shear strength and breaking torque. In an initial step, researchers have to investigate and understand the forces active in the bone structure of the foot and jaw using laboratory measurements and simulations. When the parameters for the optimum strength of the screw are defined, such as the inner and outer thickness of the thread or the radius of the thread grooves, the bone screws will be subject to real tests based on DIN standards. "In general there is a big difference between working with metal screws and screws made of biomaterial. The mechanical principles are the same, but we also have to consider that donated bone material shrinks somewhat during sterilisation and two hours after the operation expands again in the body and becomes more elastic. For this reason, we are carrying out extensive investigations and tests -- both in dry and rehydrated states," explains Sommer.

Preselection of donor material

The starting material is also crucial. The donated bone material comes from organ donors and is only allowed to be used after strict selection procedures and serological screening. Not all donated bone material is suitable for the production of bone screws. What is pivotal is the size of the Haverian canals; these are canals in the cortical bone which blood vessels and nerves travel through. The basis for the preselection of bone material was worked out using electron microscopic investigations at FELMI-ZfE ( Austrian Centre for Electron Microscopy and Nanoanalysis) Graz.


Materials provided by TU GrazNote: Content may be edited for style and length.

Disclaimer: DoveMed is not responsible for the accuracy of the adapted version of news releases posted to DoveMed by contributing universities and institutions.

References:

TU Graz. (2017, September 28). Making surgical screws from bones. Retrieved October 2, 2017.

Was this article helpful

On the Article

Maulik P. Purohit MD MPH picture
Approved by

Maulik P. Purohit MD MPH

Assistant Medical Director, Medical Editorial Board, DoveMed Team

0 Comments

Please log in to post a comment.

Related Articles

Test Your Knowledge

Asked by users

Related Centers

Loading

Related Specialties

Loading card

Related Physicians

Related Procedures

Related Resources

Join DoveHubs

and connect with fellow professionals

Related Directories

Who we are

At DoveMed, our utmost priority is your well-being. We are an online medical resource dedicated to providing you with accurate and up-to-date information on a wide range of medical topics. But we're more than just an information hub - we genuinely care about your health journey. That's why we offer a variety of products tailored for both healthcare consumers and professionals, because we believe in empowering everyone involved in the care process.
Our mission is to create a user-friendly healthcare technology portal that helps you make better decisions about your overall health and well-being. We understand that navigating the complexities of healthcare can be overwhelming, so we strive to be a reliable and compassionate companion on your path to wellness.
As an impartial and trusted online resource, we connect healthcare seekers, physicians, and hospitals in a marketplace that promotes a higher quality, easy-to-use healthcare experience. You can trust that our content is unbiased and impartial, as it is trusted by physicians, researchers, and university professors around the globe. Importantly, we are not influenced or owned by any pharmaceutical, medical, or media companies. At DoveMed, we are a group of passionate individuals who deeply care about improving health and wellness for people everywhere. Your well-being is at the heart of everything we do.

© 2023 DoveMed. All rights reserved. It is not the intention of DoveMed to provide specific medical advice. DoveMed urges its users to consult a qualified healthcare professional for diagnosis and answers to their personal medical questions. Always call 911 (or your local emergency number) if you have a medical emergency!