In the late 1940s, the biology of bone healing had not been scientifically investigated and knowledge was sparse. The book, 'Théorie et Pratique de l'Ostéosynthèse' by Belgian surgeon Robert Danis, published in 1949, attracted the attention of a young, innovative Swiss surgeon, Maurice E Müller. Maurice E Müller visited Danis in March 1950 and gathered a small group of Swiss surgeons—Robert Schneider, Hans Willenegger, Martin Allgöwer, and Walter Bandi—who shared his interests in researching bone healing.
The five founders of the "AO Cooperation" saw great potential in the internal fixation of fractured bones, which at that time was not at all well accepted by the surgeon community. From the beginning they realized that these "revolutionary" ideas would only have a chance to get into the clinics if surgeons would be taught to use internal fixation correctly (Teaching) based on fundamental knowledge about healing (Research) and well documented successful use (Documentation) and finally with applicable implants and instruments to perform the operation (Instrumentation). They declared these 4 pillars in 1959 as the main activities needed to convince other surgeons to use the new techniques of fracture treatment and started immediately to organize structures for all the 4 pillars to ensure the success of their "revolution" in fracture treatment.
The implant designs reflected the aim to achieve absolute stability and combine that with pressure on the bone to maximize healing. The central plate of this period was the standard compression plate (CP) with round holes and screws. These pressure plates came in narrow, broad, long, and short versions, as well as in the form of a tubular semi-pipe plate issued in 1963. This initial standard Instrumentarium was used in the first Davos Courses in 1960 and 1961, predating the creation of the AO Technical Commission. The use was primarily intended for long bone fractures to the upper and lower leg. Over time, additional cassettes for other types of fractures were added.
In December 1960, in a move to protect Robert Mathys and the AO, Synthes AG Chur was established to coordinate instrument production, present them to the medical community, and distribute profits. Peter von Rechenberg crafted the wording. The five founding fathers owned the 50 shares.
In November 1961, the AO Foundation established the AO Technische Kommission (AO TK) as the institute responsible for the development and approval of innovative surgical techniques, implants, and instruments. In practice, the AO TK controlled all the prerogatives Synthes catalogues and commercial material and made sure that the products offered were identical with those described in the AO textbooks. Only instruments and implants that were approved by the AO TK were allowed to be sold. When the AO TK first met, it was an informal group consisting of the four AO founders and Synthes AG Chur shareholders, together with producers Robert Mathys and Fritz Straumann. The group met several times each year, and its decisions, made by majority vote were binding for all AO TK members, surgeons, and producers alike.
The first session on December 16, 1961, was comprised of Müller (Chair), Allgöwer, Schneider, Mathys, Straumann, two of Straumann's employees (Vogt and Karpf) and Müller's wife, who until that point had handled all shipments from her home in Biel. Meetings were chaired by Müller, and the administration of the meetings was in the hands of von Rechenberg, fiscal and legal advisor to the AO and Synthes AG Chur. Discussed were all elements of the AO Instrumentarium, the surgeons' experience with new implants, and new developments. Although the producers had an exclusive contract with Synthes AG Chur, the AO TK became the forum where decisions were made on any part of the AO Instrumentarium. Effectively, neither Straumann nor Mathys could produce and market implants or instruments related to AO procedures without express AO TK approval.
Robert Mathys produced 20 full sets of the famous six boxes which contained all the AO instruments needed for internal fixation of fractures. In 1963 at the third AO Course in Davos, the guest of honor was the German traumatologist Heinrich Bürkle de la Camp (1895–1974) who had been critical of internal fixation at the 1958 German Surgical Society congress. In Davos in 1963 he conceded that AO equipment was technically superior to anything made before, especially the Müller compression plate when compared with the than existing Lane plate. He went on to praise the AO at the German Surgical Society the following year.
The technique of medullary nailing in which the medullary space is reamed out was described in 1962 by Küntscher. The instrument set seems to be effective in most situations. In cooperation with Mathys and Straumann, the AOI nail was developed. It is thin, elastic and polished internally and externally by mechanical, electrical, and chemical means. If you would like to learn about the history of the technique of intramedullary nailing, visit the homepage of Kuentscher Society by clicking on the button below.
The new plate went through the AO's usual testing procedures. The device had undergone technical trials involving experiments in tissue culture and animals, and was ready for testing on humans in selected hospitals. In 1970 the DCP was made available for all AO members and those surgeons who regularly attended AO conferences. In 1971 a DCP set was included in the standard AO product range. In order to give surgeons a choice and to be able to distinguish the effects of the change in material from those in the change of design, the DCP was produced in both steel and titanium.
AO TK approved the first CMF Instrumentarium set for general use and, in 1976 a special set of maxillofacial instruments and implants was produced. The further development of the AO concept in the field led to a comprehensive approach to craniofacial surgery in the fields of traumatology, tumor,and reconstructive surgery.
