Doing research

The aim of research in medicine is to develop a new treatment or improve an existing one. Regardless of whether it is a matter of developing new drugs, diagnostic devices or technical interventions – the new procedures often have to be tested on animals and always on humans. If the test is successful in a larger number of patients, the procedure is considered safe: Then it can establish itself as a new standard. The path to achieving this is usually long and arduous. One particularly striking example of such a development is a new form of bone fracture treatment developed by a group of doctors, researchers and engineers around the Bernese surgeon Maurice E. Müller from the 1950s onwards. It is called osteosynthesis and is now the global standard in the treatment of fractures.

The problem

Research is mainly pursued when people are generally not satisfied with the available therapy. In the 1950s, anyone who suffered an accident while driving or skiing and broke an arm or leg was usually treated in a conservative fashion: The injured part of the body would be immobilised. This was achieved by applying a plaster cast. Patients were often unable to work for a long time and often had to stay in hospital for weeks. Nevertheless, severe and permanent damage would also occur, such as shortening, mal-positioning and stiff joints. This was neither pleasing to the booming economy nor a modern, dynamic society. The interest in a quick restoration of a person’s fully functioning body was on the increase: Surgical solutions were in demand ...

The standard around 1950

Lorenz Böhler, often referred to as the "father of modern trauma surgery", published his work "Technique of Bone Fracture Treatment" in 1929. Therein, Böhler systematises the treatment of various bone fractures. Previously, he developed a new, precisely regulated procedure in Vienna to immobilise upper and lower leg fractures by means of traction. The new technique was based on his many years of practical experience, and Böhler documented the cases in detail. In the process, it turns out: This treatment produced significantly better results than older methods. The disadvantage? Those who fell ill would have to stay in hospital for weeks and still wear a plaster cast for several weeks afterwards.

The unsatisfactory alternatives

Some surgeons developed different procedures to stabilise the broken bone with screws and plates (osteosynthesis). Thus, although they succeed in accelerating bone healing, infections would also occur. The medical profession remained sceptical, especially since the procedures and instruments had not yet been standardised. As soon as a surgeon other than the "master of the method" performs the operation, there would be complications. Maurice E. Müller was particularly impressed by the method of direct fixation to the bone and went on to study it with its inventor Robert Danis in Brussels. However, Danis rejected any responsibility if others were to use his method.

The cooperation

Modern medicine is complex. It requires the cooperation of people with different specialised knowledge. Nevertheless, it is often individual figures that stand out and shape a development. The development of osteosythesis was primarily driven by the Bernese surgeon Maurice E. Müller, who, together with Martin Allgöwer, Hans Willenegger, Robert Schneider and Walter Bandi, gathered a group of other doctors around him. They believe that the principle of connection by screws and plates (osteosynthesis) can work, in principle, and remained committed to a scientific and systematic review of the technique. And so, in 1958, they founded the Working Group on Osteosynthesis Issues (AO) to research the problem and develop a solution.

The network

Müller and his colleagues knew each other through different channels, be it from school, sports or the military. Therefore, the group was strongly represented in the canton of Bern. They were not university professors at the beginning of their research, but chief physicians at regional hospitals. There they had greater freedom to try out the new methods. There was a collegial exchange that encouraged critical dialogue, even though Müller was the undisputed head of the company. He was also the one who developed the instruments. He travelled from clinic to clinic and demonstrated his latest developments during operations. He was known in medical circles as the "Köfferli doctor".

Research and industry

Müller used material from different companies in the early years. His long-term goal, however, was to standardise the process. For this, he needed a uniform set of instruments and materials. Therefore, he was now looking for a manufacturer who would develop the screws and plates for him according to his needs. Müller had a whole new set of instruments in mind, with a uniform structure and high quality. Not an easy undertaking: After all, a longer development and testing phase was to be expected before anything could be sold.

In the spring of 1958, he found a potential engineer candidate in Robert Mathys, who ran a small company in Grenchen that manufactured screws and machines. Mathys had an intuitive understanding of exactly what the surgeon needs. A fruitful collaboration went on to develop between the two. By 1960, all basic instrument sets and instruments were delivered to AO members.

The new method

In AO plate osteosynthesis, the applied plate was put under tension by a tensioner, which applied pressure on the fracture. The resulting stability would cause the bone to grow together directly without the formation of intermediate tissue. Plate osteosynthesis allowed plaster-free follow-up treatment. Patients could move their joints and would not have to lie down for weeks. Movement exercises for bone fractures were not entirely new – Danis had already introduced them. What was new was the fact that the screws, plates and instruments had become standardised and that it had now been described exactly as to how operations must be performed. The longstanding commitment of the "Köfferli Doctor" had thus paid off: Müller's great surgical experience, the technical know-how of the Mathys company and the metallurgical knowledge of the Straumann Institute in Waldenburg made a decisive contribution to the success of the new surgical technique.

The principle of the tension plate and tension screw

In the first figure, you can see how the plate is fixed with a screw on one side and a hole is drilled for the tensioner at the other end (a). Then the tensioner is mounted and the supplementary screws beyond the fracture are placed (b, c). On top of this, the broken bone is pressed firmly together by tensioning the plate (d). Finally, the remaining screws were set and the tensioner removed (e, f). After about 18 months, the plates could be removed again if they were a nuisance.

The second figure shows the tension screw which would only grip in the opposite bone and slide in the nearby bone. When the screw was tightened, the fracture would be put under pressure.

The third figure shows a model with the original instruments and implants. In the 1981 film sequence, we also see the principle of the asymmetrical screw hole, although this was developed later.

Explain and prove

Not every new method was better than the old one. The majority of new developments did not catch on because users considered the old techniques to be better. The new osteosynthesis technique also met with resistance. The AO had to win over the right people on two levels. Firstly, it had to be shown in the laboratory and in animal experiments that the basic principle could be explained scientifically and that it also worked in experiments. Secondly, it would have to be proven both in clinical trials and in scientific publications that the technique also worked reliably in practice.

Tradition and Innovation

On 24.11.1960, Müller and his AO colleagues presented the new method to a larger audience for the first time. Numerous Swiss surgeons gathered at the Inselspital in Bern. Müller reported that 800 operations had been performed. Bernese Professor Karl Lenggenhager and other colleagues remained critical: Does the bone actually grow together directly without intermediate tissue? Many years of experience had shown that osteosynthesis enjoyed only limited success and was considered both unsound and dangerous. Müller also had to admit that not all operations were successful. There were also problems and risks. However, the AO argued that its patients performed better in terms of incapacity to work and disability than those treated conservatively. During the meeting held in 1960, tradition and innovation were pitted against each other – it was still unclear as to which side the pendulum would ultimately swing...

The animal experiment: the principle works

At this stage, animal experiments had become unavoidable to ascertain what changes took place on the plate and in the bone over several weeks. The broken parts of the bone were, therefore, stabilised with a plate. Then the tension in the bone was measured and it was determined whether the healing process was progressing well, or whether inflammation was occurring. The experiments showed that the tension under the plate decreased over time: So the bone was growing together in a stable way. Microscopic examinations proved that the bone actually grew together directly and without intermediate tissue. The systematic experiments of the 1960s contributed to the method's increasing acceptance from 1970 onwards.

Document experience

Müller and his colleagues attached particular importance to the careful documentation of all operations. They used control sheets and punch cards for systematic evaluation. Another important detail was the progress controls, i.e. the proof of the long-term healing success. In 1961, the AO was already able to draw on 2000 documented cases with 20,000 X-ray images. This data contradicted the speculations of those sceptics who feared infections and poor healing. The AO went on to prove: Carefully performed operations resulted in almost no complications.

Clinical research: the statistics were right

With the emergence of so-called evidence-based medicine, the demands increased from the 1980s onwards. Surgeons needed to distinguish more precisely between individual operations. They also had to statistically compare the healing success of the chosen method with other procedures. Only then could they justify why one method is preferable to another. The AO went on to meet these demands by developing a detailed classification of the different bone fractures, specifying the corresponding surgical procedures and proving their superiority in clinical studies. In this way, the various AO procedures were to become established as best practice for surgeons to follow.

Publishing: tested knowledge

Research results were only recognised in the community of researchers if they are published. This way, anyone interested could check how the results were arrived at. Müller and his colleagues made their results known in numerous journal articles and also in books. At the beginning, such contributions were often still published in German and French. However, publications in prestigious English journals such as those of the Royal Society of Medicine were becoming increasingly important for international recognition. In the 1960s, a small group of editors would still decide whether a publication was to be accepted. It was not until the 1970s that peer review began to gain acceptance. Not only a small editorial team, but a much broader network of specialists were set to guarantee the quality of the research.

Teaching and learning

How do you learn a new surgical technique? It’s similar to riding a bike: through instruction and practice. This is referred to as "tacit knowledge" – knowledge that cannot be described precisely and cannot be learned from books. Prospective surgeons traditionally acquired this knowledge by visiting the experienced and eminent surgeons. The AO took a new approach and offered courses: This led to a much faster and greater spread of the necessary technique – now a matter of course, but still a novelty in 1960.

The Master shows how it’s done

Theodor Kocher developed a new form of extremely precise, controlled surgery in Bern: This was also the approach he took in thyroid surgery, in particular. Every year, dozens of surgeons, mainly from the USA, came to study his technique in the operating theatre. The advantage? The budding surgeon was able to watch the master operate on the living body. The disadvantages? 1. Few could really see all the steps of the operation in detail. 2. Viewers were unable to do it themselves and practice the procedure under supervision.

The course: a new form of teaching and learning

The early history of osteosynthesis revealed to Müller and his colleagues: The operation can only be repeated successfully if you know the procedure very well and can practise it. The old form of instruction in the operating theatre was not suitable for this. And so the AO would go on to offer courses. The first course took place in December 1960. 80 people take part – far more than planned. Being able to try out the new surgical technique themselves gives many surgeons the confidence that they could successfully apply the method themselves. The organisers felt vindicated by the success. The course began to establish itself as a central feature of the AO.

A new community

Strict hierarchies prevailed in the operating theatre. The course, on the other hand, created a whole new environment. Younger and older people would meet here, teachers and learners would discuss with each other, thereby leading to a flattening of hierarchies. During the course, which lasts several days, the participants also got to know each other personally. The AO deliberately promoted and cultivated this process of exchange. It organised communal meals, excursions and ski races. This promoted mutual trust and created the basis for a continuous exchange. The courses became central to establishing a community that felt connected through the AO method.

Selling technology

Research not only produced a knowledge that was available free of charge, but also cures and technologies that hospitals had to acquire. A hundred years ago, technology was still relatively simple and cheap, but since the Second World War, increasingly complex devices and instruments were produced. These were often not compatible with each other. The hospital had to decide on a system and purchase all the material for a specific procedure from the same manufacturer.

Each surgeon and his own instrument

Generations of famous surgeons developed their own instruments based on their many years of practical experience. Theodor Kocher was one of them. The Schaerer medical supply shop in Bern would sell Kocher's extensive "original instrumentarium". However, it not only offered Kocher's famous artery clamp, but at the same time the clamps of a whole series of other "masters". Each surgeon was able to assemble his or her own instruments as required. There was no uniformity.

A holistic solution

With the AO, screws, plates and instruments were precisely matched. This was the only way to guarantee accuracy and repeatability. The AO sold individual sets for different surgical procedures in five coloured cassettes. The system of coloured cassettes endured for a long time. Such total solutions were popular with surgeons and hospitals. They were also in the interest of the manufacturers: Those who opted for the system would not be so quick to change the entire set of instruments. Soon, the AO's operation sets became so dominant in the market that most competing companies had no choice but to adopt the AO's basic standards.

The new standard

A new method becomes established as a standard when the majority of the community uses it. This process is not the same everywhere and not at the same pace. There are not only scientific but also social and cultural reasons as to why one method prevails and another does not. However, if the breakthrough succeeds, a lot of money can be earned on today's international market.

Control is the key ...

To ensure the success of the AO method, the control and standardisation of the instruments and processes were very central prerequisites. During the growth phase, only those who had also completed the course could buy the instruments. It also committed those involved to documenting their own operations and forwarding the results to the AO in Davos. This created a unique, worldwide network of controlled operations. The central documentation and research centre in Davos began growing accordingly.

The GDR: a pioneer

The health authorities in the GDR regarded the accumulation of fractures caused by car accidents as a social problem that the state had to solve. And so the authorities commissioned surgeon Eberhard Sander to take care of it. Sander attended AO courses and had the system tested in the GDR by a small group of specialists. The successes led to the system being introduced under state control as early as the mid-1960s. However, it only gained limited acceptance because there was not enough money to buy the instruments.

The USA: late acceptance

In the USA, there was no pioneer group like in Switzerland or the GDR that advocated for the new method. US surgeons insisted on their independence and regarded the Swiss AO as dogmatic and a restriction on their freedom. Some even spoke of an "invasion" by this foreign method. It was not until the AO began conducting animal experiments and larger clinical trials in the late 1970s that the new technique became increasingly accepted. With its spread in the USA, the AO method became an international standard relatively quickly. Now, the great commercial success enjoyed by this approach started to materialise.

Big business

The AO was not a profit-making organisation. In 1960, the Mathys company produced under licence from the AO, followed by the Straumann company in 1963 and Synthes USA in 1974. The companies supplied money to the AO, which used it to finance research and development. The upswing in the US market was due in no small part to the skill of Hansjörg Wyss, CEO and major shareholder of Synthes. The company increasingly dominated the AO business. The AO sold it the patents for one billion francs in 2006. Wyss sold Synthes to Johnson & Johnson for $21 billion in 2011. So it's not the inventor who makes the big money, but the businessman.

The research continues ...

Research and development never stand still. If you want to stay on the ball, you have to continuously improve or fundamentally redevelop your products. The AO and increasingly also companies constantly develop new procedures for all bones. The Synthes (now DePuy Synthes) catalogue alone currently includes several thousand screws, plates and instruments. The AO is considered a recognised authority in this field. Therefore, it tests new techniques and awards the quality mark "AO approved". To continue to be accepted as a standard, these procedures must be documented and taught in courses worldwide.

New solutions

The human body has over 200 bones. They can all break in very different ways – this means pain for the injured and a challenge for the surgeon. Every bone fracture is different and accordingly the bones can be screwed differently. The AO and its associated companies go on to develop a technique for all these fractures over time. New questions keep arising, for example, how to operate as gently as possible or in cases of bone loss (osteoporosis).

Securing the standard

New methods not only needed to be developed and scientifically documented, but also taught. From the 1970s onwards, AO courses were increasingly offered all over the world. Today, 58,000 participants attend over 800 courses every year. Being able to practise the procedure on the artificial bone itself remains key. In addition, online learning has also become established in recent years. The fact that an organisation like the AO has managed to set the standard for decades is rather unusual. New researchers and companies often emerge with innovations that displace the old top dog.

Selective bibliography

The information given about the AO is mainly based on:

Schlich, Thomas (2002): Surgery, science and industry: a revolution in fracture care, 1950s – 1990s, Houndmills.

Further literature:

Heim, Urs F.A (2001).: Das Phänomen AO. Gründung und erste Jahre der Arbeitsgemeinschaft für das Studium der Osteosynthese, Bern.
Jeannet, Jean Pierre (2018): Leading a surgical revolution. The AO Foundation – Social Entrepreneurs in the treatment of bone trauma, Cham.
Schatzker, Joseph (2018): Maurice Edmond Müller – in his own words, Davos.