1947-01-01 18:21:50

AO origins

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.

1959-01-01 01:17:44

AO Founders developed four pillars

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.

1960-01-01 00:00:00

First generation Instrumentarium

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.

1960-12-01 00:00:00

Synthes AG Chur established

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.

1961-11-01 00:00:00

AO Technische Kommission (AO TK) established

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.

1961-12-16 00:00:00

First AO TK meeting

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.

1963-01-01 00:00:00

First AO instrument boxes

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.

1965-01-01 00:00:00

First AO nailing

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.

1970-01-01 00:00:00

Dynamic compression plates (DCP)

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.

1975-01-01 00:00:00

Maxillofacial instruments and implants

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.

1979-01-01 00:00:00

Dynamic hip screw (DHS)

Due to other firms like Osteo, Richards, and Zimmer starting to offer hip screw systems and threatening to lure surgeons away, the AO gave in to the pressure and one of Straumann's designers developed an AO DHS system. The device was brought out and proved to be very useful in any case and became a success, both in medical and in commercial terms.

1982-01-01 00:00:00

New AO TK Chair

In 1982 Maurice E. Müller handed over the chair of the AO TK to Stephan Perren, the Director of the AO Research Institute in Davos.

1987-01-01 00:00:00

AO TK Spine

TK Spine had previously been formed under the leadership of Erwin Morscher, the doctor who had pioneered the internal fixator. Max Aebi was pushing the need to create a separate AO chapter for surgery on the spine. By teaming up with John Webb, the two quickly moved on a parallel Technical Commission for the spine. The universal spine system was to supplant the older generations of inter-nal fixator propagated by Morscher, creating tensions between the two factions. Unofficially de-scribed as a "palace revolution" by some "young rebels" a new Spine TK was formed, receiving financial support from the AO organization and now named AO Spine TK.

1991-01-01 00:00:00

Limited contact DCP (LC-DCP)

The realization that contact of the plate with the underlying cortex led to damage of the cortical blood supply resulted in a redesign of the plate profile. The dynamic compression plate, which succeeded the round-hole plate in 1969, was replaced by the limited-contact dynamic compression plate in the mid-1980s. The limited-contact dynamic compression plate has enjoyed great clinical popularity and success. It was introduced in 1991 for the first time.

1991-01-01 12:10:59

Innovation awards

The AO Recognition Award, the AO TC Innovation Prize, and the AO Technical Commission Certificate of Merit are intended to recognize and encourage the continued pursuit of excellence, innovation, and continued rigorous improvement. The AO Recognition Award is awarded by the AO Foundation's supervisory body, the AOFB, to honor individuals within the AO TC who have made significant contributions to the AO Foundation throughout their career and achieved meaningful impact to product innovation and patient care. The AO TC's Innovation Prize is awarded by the AO TC's supervisory body, the TCEB, to recognize individuals or groups for their leading involvement and innovative contribution to a project that has made significant impact. The Certificate of Merit is awarded by the AO Technical Commission's supervisory body, the TKEB, to individuals as a sign of appreciation for outstanding activities over the course of one project or a year.

1991-12-01 00:00:00

Reorganization of the AO TK System

In December 1991 the so-called "big AO TK" decided to restructure for efficiency. A "Core AO TK" and eight Sub-Commissions (Joints TK, Long Bone TK, Material TK, Maxillofacial TK, Pelvic TK, Small Implants TK, Spine TK, Veterinary TK) were established with five surgeons in each group. Only the AO TK could approve implants and instruments which were developed and tested by the Sub-TKs.

1993-01-01 00:00:00

Point contact fixator (PC-Fix)

Further research into the contact of plates with bone led, in 1987, to the development of the point contact fixator. The PC-Fix has even less bone contact than the limited-contact DCP and can be understood functionally as a completely implanted external fixator. Due to the avoidance of bone necrosis, the PC-Fix reduces the risk of infection and reduces healing time from 18 months with conventional plates to some three months. The surgery itself takes about 15–20 minutes less.

1995-01-01 00:00:00

The less invasive stabilization system (LISS)

Since the PC-Fix can only be used in certain parts of the bone, another system based on the same principle called "less invasive stabilization system" (LISS) has been developed. A whole new family of fixation devices has been developed from this concept of locked internal fixation. LISS plates or the distal aspect of the femur, the proximal part of the tibia, and the whole family of locked compression plates are examples of these devices. Several clinical trials using these implants are ongoing.

1995-12-01 00:00:00

First AO TK Guidelines

In December 1995 the AO TK approved the first AO TK Guidelines to ensure proper functioning and information management in the AO TK and its sub-groups. New Study Groups (Foot and Ankle SG, Knee SG, Shoulder SG) were established and the Joint TK was dissolved, both to better reflect the surgeons' community in specialization.

1997-01-01 00:00:00

Minimally invasive plate osteosynthesis (MIPO)

The techniques of indirect reduction and application of a bridge plate have resulted in the development of the concept of minimally invasive plate osteosynthesis (MIPO). In this technique, the fracture is first reduced by indirect means. The plate is then slid through a small skin incision, deep to the investing muscle, and when the plate is in position, it is fixed to the bone with screws inserted percutaneously. This technique of plate fixation mimics intramedullary nailing with the obvious difference that the fixation device, ie, the plate, lies in an extramedullary position. In metaphyseal regions, minimally invasive plate osteosynthesis has advantages over a conventional open plate-fixation techniques.

1998-01-01 00:00:00

New AO TK Chair

In December 1998 Norbert Haas takes over from Stephan Perren who has led the AO TK since 1982. The Approval Process with defined Milestones was established and formulated in the new AO TK Guidelines.

2000-01-01 00:00:00

Locking compression plates (LCP)

The locking compression plate (LCP) was the final step of this creative development period that combined previous features of compression plating (LC-DCP) and locking plating (PC-FIX/ LISS) by a newly designed combination hole. The use of compression screws allowed for fracture compression; the use of locking screws provided angular stable locking of screws. The advantages of using the LCP with locking screws allowed the surgeons to use the plate with less exposure to the bone (bone bridging technique) and increased the implant anchorage in osteoporotic bones. Robert Frigg, Michael Wagner—a surgeon—and Robert Schavan, biomechanical engineer, led the development of the LCP.

2001-01-01 07:45:09

First issue of the TK News Magazine

The AO Foundation identified a demand for information about innovations and the clinical advantages of its new products. The TK News aims to provide and overview. In addition, some interesting surgeons, groups, and their achievements are presented.

2003-12-01 00:00:00

First AO Spine TK Meeting

In December 2003 the newly established AO Spine division held its own first AO Spine TK meeting. The new group consisted of the "normal" AO TK members governed by the AO Foundation and some spine surgeons.

2004-01-01 00:00:00

Collaboration with BrainLAB initiated

The AO Foundation agreed to the collaboration between the German-based company BrainLAB and the dedicated expert group for computer assisted surgery (CSEG) to develop software modules for intraoperative navigation.

2004-01-01 22:26:36

Prize for lifetime achievements

In 2004 Stephan Perren is awarded the AO Innovation Award for his lifetime achievements and exceptional contributions to the development of new concepts, technologies, and treatment options.

2005-01-01 00:00:00

AO TK Executive Board

In February 2005 the AO TK agreed to split up the AO TK into Specialty TKs, reflecting the changes in the AO Foundation where new specialties/divisions were established for Trauma, Craniomaxillofacial and Veterinary. The Veterinary Expert Group decided to stay under the AO TK, which from now on will be called AO TK Trauma, whereas the AO TK CMF was established as a new group with its own sub groups similar to the structure of the AO Spine TK. The AO TK CMF had its first meeting in June of the same year. To govern the whole AO TK System, as it is to be called from now on, the AO TK Executive Board was established having the AO TK Chairs as voting members.

2006-01-01 00:00:00

New contract with Synthes

The new contract defined AO TK System as part of the collaboration agreement. The new structure with AO TK Executive Board, Specialty AO TKs, Expert Groups, Working Groups, and Task Forces as defined in the newest AO TK Guidelines is now part of the bylaws of the AO Foundation as well as the collaboration agreement with our development partner Synthes.

2007-01-01 07:00:00

TPLO system

Launched in 2007, the veterinary tibial plateau leveling osteotomy (TPLO) system revolutionized the surgical treatment of cranial cruciate ligament (CrCL) injury in dogs, leading to improved outcomes and reduced complications for the most commonly performed elective osteotomy in canine patients. The slope of the canine tibial plateau is much greater than its human counterpart, which results in increased loads on the canine CrCL. Cranial cruciate ligament (CrCL) injury is the most common cause of hind-limb lameness in dogs and is frequently treated with TPLO. The TPLO procedure dynamically stabilizes the knee by eliminating cranial tibial subluxation during the weight-bearing phase of locomotion. The TPLO system combines a locking plate with a basic instrumentation set including jigs and saw blades.

2007-01-01 22:56:08

First three navigation modules approved

The AO TK (Trauma) approves the first three navigation modules successfully developed by the expert group for computer assisted surgery (CSEG) in collaboration with the German-based company BrainLAB.

2008-01-01 22:46:04

4.5 mm locking compression plate

Launched in 2008, the veterinary 4.5 mm locking compression plate with stacked combination holes transformed the surgical procedure for proximal interphalangeal (PIP) joint arthrodesis in horses. Arthrodesis eliminates joint motion and may be performed to treat osteoarthritis of the PIP joint, a common cause of equine lameness. To achieve effective arthrodesis in the treatment of degenerative disease of the PIP joint, this plate has an extended center section that spans the joint space. The stacked combination hole prevents impingement on the extensor process of the distal phalanx. Following arthrodesis, a high percentage (up to 75% in the forelimb and 90% in the hindlimb) of equine patients are able to return to their intended performance activity. Compared to the standard locked plate design, the toenail design at one end of the plate was eliminated and the most distal hole changed from a combination hole to a stacked combination hole. These changes allow the plate to be placed as close to the joint as possible. In addition to its use in arthrodesis, the veterinary 4.5 mm locking compression plate (narrow and broad) is also indicated for long bone fractures and metaphyseal fractures.

2009-01-01 00:00:00

New AO TK Chair

In December 2008 Tim Pohlemann takes over the lead of the AO TK System from Norbert Haas.

2011-01-01 12:35:57

50 years AO TK System

AO TK System celebrate its 50 year anniversary. At the AO Davos Courses, Stephan Perren shares a few memories of how it started on a slide presentation and encourages the members to remain enthusiastic and critical, both key to success.

2011-01-01 22:36:23

Meet the Experts

Excellence in innovation on display. Since 2011 this popular format offers the opportunity to learn about the AO TK's most recently approved medical devices and to explore hot topics in trauma and orthopedic surgery. The sessions showcase clinical benefits of innovative devices and surgical techniques which are so new that they have not yet been included in AO course programs. In an engaging series of stage shows featuring practical demonstrations, expert surgeons present clinical cases and explain the benefits of new solutions for patient care. The sessions are streamed live and available thereafter on the AO website.

2015-01-01 00:00:00

New opportunities for off-ramp partnerships—adapted AO TK Guidelines

In 2015 a new collaboration agreement was signed between DePuy Synthes and the AO Foundation giving the AO TK System some new freedom in developing out-of-scope solutions with new development partners. This new option offers the AO TK System to widen the scope of activities beyond the collaboration with DePuy Synthes into new areas of interest. Since 2015, the AO TC has developed new workstreams to guide the process of collaboration with "third parties" (alternative industrial partners) in the realization of "off-ramp" projects (projects declined by DPS).

2016-01-01 00:00:00

First AO TK Neuro meeting

The AO TK Neuro has its first meeting in July. The newly established AO TK Neuro comprises an international group of neurosurgeons. Neurosurgery had grown in importance as a clinical discipline within the AO since the mid-1980s. The new TK allows the AO to extend its activities into the development of products for the treatment of neurological and neurovascular disorders. The aim of the AO TK Neuro is to oversee project teams focusing on development projects in specialty areas such as neurotrauma, cerebrovascular surgery, and skull base surgery, and to review products for eventual TK approval.

2016-03-01 00:00:00

New AO TK Approved Solutions website

March 2016 saw the launch of the AO TK System's brand new AO TK Approved Solutions website. Showcasing surgical products that have been approved by the AO TK System. It was constructed using state of the art responsive design, meaning it can be viewed in high-quality on all popular browsers and devices. Filters allow the user to search the site according to areas of interest including anatomical region, product type, and approval date. Users are able to access comprehensive product information, including relevant clinical cases, surgical image galleries, and descriptions of associated instruments.

2017-01-01 00:00:00

New AO TK Chair

In December 2017 Daniel Buchbinder takes over the lead in the AO TK System from Tim Pohlemann being the first CMF surgeon after decades of leadership by Trauma surgeons.

2019-12-01 10:16:06

Signing of the first off-ramp contract

The AO Foundation and icotec ag announce the successful agreement and kick-off for the joint development of a new spinal stabilization system based on icotec's proprietary BlackArmor® Carbon/PEEK composite implant material.

2020-01-01 00:00:00

New structure and change to AO TC naming

The AO TK System became part of the AO Innovation Translation center and was renamed the AO Technical Commission (AO TC). The AO TC is the AO's innovation driver. The focus is on introducing change and new ideas into all areas of the organization's practice by taking interdisciplinary collaboration to a new level, improving its overview of clinical needs, and achieving greater flexibility in its core structure. The existing concept of the Expert Groups and Task Forces will be carried forward into the new structure. The flexibility will be one of the key factors in its continued success.

2021-11-01 00:06:24

AO TC turns 60

AO TC turns 60 in November 2021 and celebrates its anniversary at the annual AO Davos Courses in December. A short video with a review of important milestones in the history of the AO TC has been created. Take a look!

2022-06-25 15:07:37

New AO TCEB Chair

As of June 2022, Maarten Spruit is the first Spine surgeon to lead the AO TCEB. He succeeds Daniel Buchbinder.


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