HOME    NEW ARRIVALS     MONTHLY SPECIALS     ABOUT US    NEWS    CONTACT US     MARTIAL ARTIST     EVENTS     BRAND     FACEBOOK    TWITTER

Sunday, March 13, 2011

Designing a sling.

Immediately after my accident my arm was limp and hanging from the shoulder. It was heavy, weighing much more than it does now and causing a great amount of discomfort and pain. Because the shoulder muscles were no longer active, the tendons and ligaments took the weight of my arm and eventually subluxation would occur (dislocation of the shoulder). To prevent this from occurring my occupational therapist organized a sling for me.
The idea of this sling is to act like a harness, supporting the weight of the arm at the elbow and taking the pressure off the shoulder joint. It distributes the weight across both shoulders (the harness) and by all accounts worked really good at this simple task. Unfortunately the sling was not designed for running, jumping or any quick movements as the arm would quickly fall out. It is also not so aesthetically appealing, it only comes in white and is not exactly fashionable, hence why I tried dying it black.
I remember two months after the accident, writing my list of life goals that I wanted to achieve before I was perhaps incapable of doing so. On top of that list was "grade for my black belt". To do Taekwondo I was going to need a sling which secured my arm in place as though it was strapped to my body. I needed something that complete immobilized the flail limb so that I was not distracted by it moving around in awkward or uncomfortable positions or falling out of the sling itself.
I approached my occupational therapist and together we had a number of rehabilitation businesses come and discuss what sort of sport slings might by available to purchase. It was a dead end with one rep actually saying "I shouldn't be doing any sport in my condition".
Eventually I was directed to an Orthotist, Steve Owen. His job is to design a solution to a bio mechanical problem. He deals with all sorts of sports injuries and physical impairments to create and build equipment which aids people in there daily lives.
He looked at the sling I was wearing and used this as a guide to plan a design that would solve my problem. The sling was going to be more durable, made out of a soft plastic to support the arm (which is a cast of my arm so it fits perfectly) and thick harnesses with plastic buckles.
We encountered a number of problems such as how do I get it on and how can I tighten it myself without the aid of other people.
The first design needed to be completely adjustable as we weren't sure as to how it would best sit on my body. Therefore every fixed joint was made out of Velcro. It was completely white in color and it tended to move around a lot.
To solve this I had a large (200mm high) Velcro elastic band which someone would wrap around my entire body and sling. As you can imagine training with this on was not easy. It was hot and very restricting.
Two years later the second sling evolved (pictured right). Steve told me he could get the plastic in black now and I jumped at it. The problem with having only one sling which is white is it gets dirty, looks dirty and is very hard to clean.
It is very similar to the original but we moved the buckle (attached on the plastic arm support) closer to the elbow. You can see on the harness (left of the sling) is the attaching clip for the buckle which I clip into once the sling is on my shoulders. This repositioning helped to remove the need for the large Velcro elastic which surrounded my body.

Steve is not a big one for changing designs if something works, as many of his clients get so accustomed to what they have that any differences is not accepted easily. I'm much the same but then again I'm also constantly looking to improve the sling to increase its functionality and improve my chances of winning in any way I can. Lets face it, I need every advantage I can get.
Left is sling number three. To put it on I first place my arm inside the cast and do up one small Velcro strap around the wrist (to prevent my arm from falling out of the cast). Secondly I pull the harness over my left shoulder and then slide my arm into the loop on the right (best seen on the second picture). Then I clasp the buckle on the right strap to the cast locking the sling in over my shoulders and around my body. The two straps in front of me are connected to two buckles which I pull on to tighten the sling so it is immobile.
The main difference of this sling to the other two is the finishing position of my left hand. In the first sling my arm was horizontal around my body, add a chest guard to this and basically the scoring area for my opponents is like kicking a goal from two meters in front of the goal line. To easy not to score.
You can see with this design, the hand placed high out of the way I'm attempting to have the chest guard fixed as close to my body as possible and not give my opponents that extra inch to score on.
The sling has ultimately given me the freedom to do what I love and to do it to the best of my ability. It is however a burden, uncomfortable to wear, restricts my breathing as it is tight across my chest, needs constant washing and still provides a distraction when it shifts out of position and therefore needing re-adjusting.
That leads to a further question. Do I amputate?

No comments:

Post a Comment