Heinz Mittelmeier died on 15.07.23 in his house in Homburg/Saar. Born on 09.10.1927 in Ingolstadt, he grew up in Bavaria, skipped 2 school classes and graduated from high school at the age of 16. He was seriously injured by shrapnel during the World War II. He studied medicine in Munich, passed the state examination in 1953 with an excellent grade, and obtained his doctorate summa laude in 1954. After completing his pathology studies in Munich, he moved to Berlin in 1957, where he worked with A.N. Witt. In 1956, he published the world’s first systematic work on particle disease caused by endoprostheses, ultimately achieving habilitation in 1961. In 1964, at the age of 36, he became the chair of the Orthopaedic University Hospital in Homburg. At the time of his retirement in 1996, he had developed this clinic into a renowned global centre for endoprosthetics.
He developed the first dynamic orthosis for hip dysplasia and improved the surgical treatment using a “metal hip clamp”, which is still widely used today as a “self-tightening angle pressure plate”. Together with his son, he developed bone substitute materials from processed or ceramized animal bone (Collapat, Pyrost) and introduced these materials into broad clinical application (Fig. 1).
He gained worldwide fame for developing the first cementless hip stems with a rectangular cross-section and a large surface area (autophor). He patented the first screwed cup, initially for ceramics. With Feldmühle, later CeramTEC, he laid the basics for more stable ceramic components and introduced ceramic inserts as safe ceramic pairings worldwide. He realized that ceramic head breakage could be prevented by changing the design of the inside of the head and standardizing the cones. Through his involvement in the committee for standards in arthroplasty (DIN/ISO), the Euro standard cone was established.
He was the president of the German Orthopaedic and Traumatologic Society (DGOT) later DGOOC (Deutsche Gesellschaft fur Orthopaedie und Orthopaedische Chirurgie). In 1974, he became a member of the German Society for Plastic & Reconstructive Surgery. In addition to other roles, he served as a board member of the German Federal Medical Association (BÄK). In 1987, he presciently founded the AFOR Foundation as a discussion platform for orthopaedics and traumatology (Fig. 2).
For many years, he had a close friendship with numerous Polish colleagues and was actively involved in the German-Polish Circle of Friends of Orthopedics. He invited numerous young Polish colleagues to his clinic in Homburg-Saar and encouraged them in modern surgical orthopaedics and biomechanic research.
He has received numerous scientific awards and 25 honorary memberships of international professional societies, including the Order of Merit of the Federal Republic of Germany. However, the award of an honorary doctorate from the University of Gdansk was his most appreciated acknowledgement.
He always supported his employees, specifically in research and clinical practice. To his 4 sons and pupils, he was a kind and fair father, setting a solid example while maintaining strictness. He changed the orthopaedic landscape in an internationally unique, fundamentally creative and forward-looking way. We thank him infinitely [1-4].

Univ.-Prof. Dr.med.habil. Wolfram Mittelmeier
Prof. Dr.med. Heinrich Hess

Addendum

Professor Heinz Mittelmeier, Head of the Orthopaedic Clinic of the Saarland University in Homburg, maintained excellent relations with Polish orthopaedists, which resulted in educational and scientific trips to Homburg by numerous orthopaedists from Poland, who had the opportunity to observe the Professor’s daily work but also had the opportunity to learn about new surgical techniques.
At the time, the Professor’s introduction of a ceramic cementless hip endoprosthesis was a groundbreaking innovation. Such endoprostheses were also used in Poland, and to this day one can still see patients with such an endoprosthesis.
The culmination of Professor Mittelmeier’s activity in Poland was the conferment on him of the title of Doctor Honoris Causa on 26 March 1993 at the Medical Academy in Gdańsk. The supervisor was Professor Józef Szczekot (Gdańsk), and the reviewers were Professor Antoni Hlavaty (Gdańsk), Professor Romuald Kreczko (Warsaw) and Professor Antoni Wall (Wrocław) (Fig. 3).
In remembering Professor Mittelmeier, it is also worth mentioning Dr Michał Grabowski, who worked at the Department of Orthopaedics of Medical Academy in Gdańsk and then with Professor Mittelmeier in Homburg. Dr Grabowski was the “bridge” between German and Polish orthopaedists, especially between Professor Mittelmeier and orthopaedic surgeons in Gdańsk[5-6].

Professor Tomasz Mazurek MD, PhD