Welcome to our viewers from IF: Oxford. We've put all our family friendly resources on the Oxford Biopatch in this blog post. Do let us know if you have a go at the crafting activities described at the end of this page.
What has the ancient craft of weaving got to do with modern techniques for healing?
Scientists at the University of Oxford are pioneering a new way of encouraging shoulder repair. The muscles in our body are attached to our bones with tendons. Sometimes the tendons in our shoulder get torn, particularly those in a group of tendons in our shoulder known as the rotator cuff. This makes the shoulder painful and difficult to move. People with damaged shoulders can get surgery to try to mend the damage to their shoulder and this is currently done by sewing the tear together with standard surgical thread but researchers would like to find new ways to make the tendons heal better.
Rotator Cuff Tear by Nucleus Communications www.nucleusinc.com licensed under CC by 4
Researchers from the University of Oxford have created a new type of patch which holds the tear together and at the same time helps the body to mend the tear by encouraging it to build new tendon material on and around the patch. This acts in combination with normal surgery to improve the healing of the tendons. The patch has a special surface which encourages the body's own cells, and new tendon material to grow around and through it. The process used to create this material is known as electrospinning, this creates fine fibres which mimic the natural structure of tendon within the body.
Electron Microscope picture showing artificial elecrospun material (left) vs natural tendon (right)
(Tendon Image: Yin et al. (2010) Expert Opin. Biol. Ther 10(5):689-700))
The patch comes in three parts:
- A thin but flimsy electrospun layer which encourages new tendon growth by mimicking the physical structure of our body’s tendons, so promoting healing and regrowth.
- A woven layer which makes the patch mechanically stronger and easier to sew into place.
- A binding layer which joins the other two layers together
The whole patch dissolves slowly in the body and is completely gone after a few months, leaving the newly healed tear behind.
The production of the tendon mimicking layer uses a new form of technology known as electrospinning. However, when it came to producing the layer used to provide strength, scientists turned to a much older form of technology, the loom.
Image showing Donegal Tweed fabric (left) versus woven component of the Oxford Biopatch
(Donegal Tweed image by Toxophilus licensed under CC by 4)
265 thin strands of a degradable biomaterial can be woven into a strong fabric to form the woven component to BioPatch. In the early stages of development and testing the woven material was hand woven in small quantities on a traditional wooden table loom (similar to the one in the pictured below).
Wooden table loom for hand weaving (left) vs metal loom for automated weaving in a clean room (right)
(Wooden table loom image by Pschemp licensed under CC by 3)
As the research progressed, the manufacturing process has been automated and takes place in special ‘clean rooms’ which control the environment in which the materials are produced to ensure the patch is safe for implantation.
Currently the patch is undergoing pre-clinical testing to make sure that it is suitable for implantation in the human shoulder. Once this testing is completed it is the aim of the researchers to conduct a first in human trial to confirm the patch is safe and easy to implant into patients and provides the improved healing of tendon for which it was designed.
Weaving Wounds CRAFT – Practice your weaving techniques
You will need
Some coloured paper or thin card, scissors, ruler, pen
Set up your warp
On one of your sheets of paper/card draw a horizontal line about 2cm from the top edge. If your paper is rectangular it is a bit easier to have the paper oriented in ‘portrait’ mode. Then draw vertical lines from the horizontal line to the bottom of the paper about 1cm apart. Then cut the paper from the bottom edge along the vertical lines as far as the horizontal line. You should end up with a solid strip of paper at the top with long strips hanging down. In weaving the vertical strips/threads are known as the warp.
Weave you patterns
Cut one or more additional sheets of paper into long strips about 1cm wide. Make sure your strips are longer than the warp is wide. Now you can weave you strips into the warp. Start by going under the first vertical strip then over the next one then under the next etc till you get to the end of the row. Once you’ve done this push it up as far as it will go (the first one will be next to your horizontal line). Then with the next strip of paper start by going over the first strip then under the next and so on and, again, when you get to the end of the row push it up so it is next to the first strip. Keep going till the warp is full of horizontal rows. The horizontal strips are known as the weft.
Try new patterns and colours
Once you’ve got the hang of the basic pattern try using different colour strips to build up a striped piece of weaving. You can also change the pattern by changing how many threads you go under/over at the same time. The Twill pattern below is created by going Over2, Under2, Over2 etc for the first row, then Under1, Over2, Under2 etc for the second, and then continues moving the horizontal strip pattern one over each time.
There are lots of different patterns including basket weave, herringbone, diamond etc which you can find instructions for on the internet.
Once you’ve tried this activity, have a go at weaving your own cloth on a cardboard loom as described in the next section.
Weaving Wounds Craft – Weave your own patch
You will need
Corrugated cardboard from a cardboard box
Extra Strong thread/Thin string/Dental Floss etc
A needle with a large eye (or you can make one with a paperclip)
A ruler, some scissors, some sticky tape, a pen
Section 1 - Making the cardboard loom
Cut a square piece of corrugated cardboard with sides about 7-8cm long. Turn the card so the corrugation lines go from top to bottom as shown and draw two horizontal lines one centimetre in from the top and bottom edge.
Then cut regularly spaced vertical slits from the top and bottom edges to the horizontal lines.
Here, the corrugation marks have been used as a guide, but if you can’t see them then draw your own vertical lines about 0.5cm apart. Using the extra strong thread thread the loom. You need to go up and down at the front, but loop round the back of each of the cardboard ‘teeth’ rather than going up and down at the back (see picture below).
Once you’ve finished stringing the loom tape the two loose ends to the back.
You have now finished building and stringing the loom
If you can’t find extra strong thread, then something like dental floss or thin string will do. Normal thread is much more likely to break. You can use wool/yarn, but it is much easier to use something less stretchy and fuzzy.
If you are buying something specifically for this activity then ‘cotton warp’ is designed for this purpose.
Section 2 – Weaving the patch
Thread your wool through the vertical strands of threads, known as the warp, alternating going over and under the thread as shown in the picture. Leave an end of about 5-10cm (you can see in the picture it has been tucked round the end tooth). If you don’t have a large needle then you can use an unraveled paperclip bent into a needle shape, but it is a bit more fiddly. Once you get to the end of the row, pull it tight and come back the other way making sure that you go under the threads where you previously went over and over where you previously went under. The horizontal rows are known as the weft.
If you run out of wool or want to change colour, you can just knot the new wool to your old wool. This works best if you are joining wool of the same/similar colour. A neater alternative is to continue to the end of a row and start the new row with a new colour as if you were starting again. The end of the old wool can then be threaded through the previous weaving to hide it (once you’ve threaded under 4 or 5 rows you can just cut off any excess).
Once you are happy with your weaving then weave in all the loose ends as described above. Then carefully bend the teeth of the cardboard loom to pull the loops of cotton thread off. You can very carefully feed the thread through the weaving in order to tighten it up (a bit like you do when altering uneven shoelace lengths) but this is tricky. An easier alternative (if your loops are long enough) is to cut and knot them as shown above.
Hints and tips
When you pull the wool tight at the end of each row, this will tend to pull the whole piece of weaving inwards so you end up with an hourglass shape. One way to reduce this is to put your needle in near the end of the row and tighten against that rather than the warp threads. For a tighter weave make sure that you push your work up regularly against the previous weaving. You can use a kitchen fork to do this, or just the needle.
To create striped work with far less effort you can buy ‘self striping’ yarn which changes colour regularly as you weave.
Once you’ve got the hang of the simple under/over pattern, you can try some different styles. You can find information on weaving patterns like twill, houndstooth etc on the internet.