The Ultimate Fit for Prosthetic Legs and Feet: Symphonie Aqua System

prosthetic legs casting system

The World Leader in Advanced Limb Replication

Sam Santa-Rita, SRT Founder

In 2015, Andreas Radspieler, the inventor of Symphonie Aqua Systems, travelled from Germany to Indianapolis to show SRT his new invention. His visit forever changed SRT and is revolutionizing prosthetic care around the world. The senior clinical team met with Andreas and listened skeptically as he described his new invention. He passionately explained how he had successfully managed to capture the exact shape of the amputated limb under full weight bearing. In essence, Andreas had cracked the code to limb health and comfort.

The History:

For generations, prosthetists have been trying to design sockets that provided comfort and stability while a patient stood and walked. Early pioneers in prosthetics worked one on one with their patients, carefully carving a socket out of a block of willow wood. Each socket had to be unique to accommodate the shape of the patient’s limb or it would be too painful to stand or walk. Comfort was critical because work on the farm was difficult and walking on unpaved streets in the city was treacherous. People walked everywhere and there were no social programs to assist people that could not work.

In more recent years prosthetists began using plaster bandages to replicate the shape of a patient’s limb. Although the use of plaster bandages seems simplistic, it was revolutionary and yielded better results and was more efficient than carving wood. Each prosthetist worked carefully with his patient and through years of trial and error, experience was gained in molding the plaster to capture the shape of the limb and accommodate the challenges that scars and sensitive nerves present.

In the 1980’s, computer aided design, CAD, was introduced but still relied on the prosthetist to mold the limb with plaster. The inside of the hardened cast was traced by a computer and the shape was displayed on the monitor for the prosthetist to modify using a mouse instead of hand tools. In the 1990’s, digitally scanning the plaster cast or the patient’s limb was introduced. While scanning can accurately replicate a patient’s limb shape, it cannot account for the different densities that exist in the limb. For example: fatty tissue, muscle tissue, scar tissue, and skin all compress differently under pressure and bones don’t compress at all. The problem has always been how to account for these differences in density while weight bearing in a prosthetic socket? We now have the answer: Symphonie AquaSystem.

Learning about the Symphonie:

SRT’s senior staff knew the short comings of molding a limb the traditional way, but we never had a better option until now. Andreas had our full attention but years of experience had taught us to proceed cautiously so we asked for a demonstration. One of our senior clinicians, Shawn Brown, is a below the knee amputee. We decided that Andreas would cast Shawn and our technicians would make a socket based on the Symphonie mold. During the casting, Shawn placed all of his weight on his amputated side, doing so, comfortably. This was life changing for both the prosthetist and the patient. Once the mold hardened Shawn took his weight off of the Symphonie and removed the cast from his limb. The shape was very unique. We had never seen a cast that captured the differences in tissue density and it looked very different than anything we had ever made. Our technicians quickly fabricated a socket based on the Symphonie mold and prepared it for a test fitting. Before placing the socket on Shawn, Andreas gave clear instructions and set expectations. He said that it should not be expected to be a perfect fit, but an excellent start to a comfortable fit. The socket was placed on Shawn’s limb and he carefully transferred some of his weight on to the socket. There was no pain…yet. More weight was transferred to the socket until all of his weight was being supported by the Symphonie socket. Still no pain…only comfort. At this point we knew this was revolutionary. SRT immediately placed an order for seven Symphonie systems. This was the first multi-unit order for Andreas and SRT was the first company world-wide to place a Symphonie in every office. That was in 2015.

Symphonie is revolutionary, but not magical. 2015 and 2016 were test years. Our clinicians shared successes and failures as we learned how to best utilize this new system. We refined techniques and put a process in place for achieving clinical success.

Old habits die hard. Not all of our prosthetists consistently used the Symphonie. Some abandoned it after a few attempts because they achieved better initial results using methods that were familiar to them. On the other hand, some prosthetists were using the Symphonie almost exclusively. They persevered through the learning curve and were achieving excellent outcomes.

In December of 2016, the senior clinical team met to address the issue of inconsistent use by our practitioners. We decided to put the Symphonie through a rigorous test to prove once and for all that this should be our company- wide primary casting technique.

The Challenge:

In January of 2017, we gathered for our annual company-wide clinical training. Three patients were brought in to assist in our testing of the Symphonie. It was agreed that we would have three very experienced senior prosthetists cast the patients using traditional methods that had yielded excellent results over many years. We also decided that our three least experienced prosthetic residents would cast the same patients using the Symphonie system. Each practitioner would then modify the cast and mold to the best of their ability and have our technicians fabricate a clear diagnostic socket. SRT prosthetists are very prideful of their work so we knew everyone would give their best effort.

Round 1:

Sixteen prosthetists and many technicians gathered in the upper level gym of the National Prosthetic Center in downtown Indianapolis to participate and observe the testing. The senior clinicians went first and finished quickly. The prosthetic residents moved a little slower, but followed our Symphonie protocol. By the time the residents finished and made their way to the lab, the senior prosthetists were finishing their modifications. The goal was to have the diagnostic sockets fabricated and ready to fit immediately after lunch. Of course, the senior clinicians and residents were talking smack about whose sockets would fit better and those observing were taking sides and adding fuel to the fire. This friendly bantering continued through lunch.

Everyone is usually sleepy and moving a little slower after lunch, but not that day. We were all anxious to see the results for ourselves, even if we thought we knew what the outcome would be. Practitioners had chosen sides but remained open-minded because the test was legitimate. Senior staff versus residents is hardly a fair fight, but one cannot hide from the results.

The socket for patient number one was ready and the senior prosthetist went through the entire fitting process in front of everyone. The socket was very good, but had several areas that needed to be adjusted. Other prosthetists joined in and did their own checks to make sure nothing was missed. Next the resident applied the Symphonie socket to the test patient. The fit was also very good, but needed fewer adjustment than the senior prosthetist’s socket. Symphonie wins round 1.

Round 2:

The second socket was fit in the same order; senior prosthetist first with others checking all work. This socket fit very loose. Several layers of socks corrected the fit but how did that happen? Ninety percent of the time the socket fits with 1 or 2 ply of sock. We speculated what might have happened, but no definitive answer was found. Things happen. The resident applied the Symphonie socket and the fit was close. Multiple layers of socks were not needed and the patient was very comfortable. Round 2 goes to the Symphonie.

Round 3:

Round three was identical in the order and testing to the other rounds. The first socket lacked total-contact at the bottom of the socket. Comfort was good but the long-term effects of a socket lacking total contact are not good. The second socket was excellent. Minimal adjustments needed to be made and comfort was superior to the first socket. Symphonie wins the third round.

The Results:

The decision was unanimous, with Symphonie winning all three rounds. Our discussion was lively and no one protested the results. It was clearly demonstrated that the Symphonie system, using our protocol, provided a better initial fit than experienced prosthetists using traditional methods. The question was then asked, “Did any of you senior clinicians feel confident and experience success in less than ten castings? Did anyone feel confident after 20?” The answer was, “No!” We also agreed that 100 castings do not make you an expert. There is no substitute experience regardless of what you are doing.

As of January 2017, the Symphonie Aqua System is SRT’s primary method for replicating limb shape under weight bearing. It is not our only method of capturing a limb’s shape. We still use traditional methods and digital scanning when appropriate. Not all patients are strong enough to use the Symphonie system because they must stand and bear weight on the amputated side. Some patients have very sensitive limbs and need therapy prior to casting, which is why SRT still uses other methods.

I have never shared the detail, thought, and testing that goes into any new product or method before we implement it within SRT. However, Symphonie is not just another hot product or new technique. I started working in prosthetics when I was 12 and have been a certified prosthetist for 23 years. I have witnessed major advancements and many gimmicks during that time. Microprocessor knees, feet, ankles, elbows and hands are definitely life changing technologies, but nothing is more essential to a successful independent life than a well-fitting socket. As a prosthetist, I have never been more excited to bring a new technology to my patients. Symphonie will change prosthetic care and expectations throughout our profession. Prosthetists will be either on board or left behind. As we were wrapping up our testing, one of our prosthetists made a profound, yet honest comment. “It’s not fair that a resident or an average prosthetist can now get the same results as I do. I’ve worked hard to be good at my job.” The senior staff had already thought of this and the answer was “So what? Is this about you or about the patient?”

Symphonie is only one piece of the puzzle and new technology in the hands of average prosthetists will always yield average results. The SRT staff works hard to be the best they can be and they don’t let the difficulty of change stand in the way of progress.

This year SRT celebrated our 15th anniversary. While that is an accomplishment, I can’t help but think, “So what?! It’s just a number. It’s not about us, it’s still about our patients. ”Now that is something to get excited about!