Principal investigator: M. Bachy

Investigators: J.C. Aurégan, M. Bensidhoum, T. Hoc, E. Potier, L. Rouquier, G. Xiong

Biomedical innovations in orthopaedics have always been based on a multidisciplinary approach with a strong biophysical component. Even more so today, clinical research in orthopaedics must integrate advances in biology (through cell therapy), advances in physics (with new and often connected analysis technologies, their miniaturization, and big data processing) and advances in surgery. The three projects below are part of this ground-breaking innovation approach whose objective is to improve patient well-being and quality of life.

1/ Improvement of quality of life for patients with osteogenesis imperfecta

Image en 3D d’un os cortical sans (gauche) et avec (droite) ostéogenèse imparfaite

Osteogenesis imperfecta, commonly known as “brittle bone disease”, is mainly due to a genetic mutation affecting collagen (main organic component of bone tissue). For these patients, a low-intensity shock, which would be inconsequential in healthy subjects, may result in a bone fracture. In recent years, bisphosphonate-based treatments targeting the reduction of osteoclast (cells resorbing bone tissue) activity have been prescribed to limit the risk of fracture. A complementary step would be to increase bone formation. In-vitro studies on mesenchymal stem cells suggest that mechanical stimulation of these cells increases their collagen production. The present project could help medical teams to offer osteogenesis imperfecta patients a personalized physical exercise protocol to stimulate bone formation.

2/ Induced membrane surgical technique

Radiographie montrant la technique de la membrane induite pour la réparation d'un défaut osseux

This technique, commonly used in adults to treat major bone loss, mainly of traumatic origin, is also used in paediatrics to treat bone tumors in children. This surgical technique requires two distinct operating times. (1) Initially, the bone defect is filled by a cement spacer that will induce the formation of a membrane around the cement, giving the name to this technique of “induced membrane”, created by Professor Masquelet. (2) In a second operating time, the membrane is gently opened, the cement is removed, and the resulting cavity is filled with a bone substitute. The objective of this project is to develop connected, physical tools for monitoring the mechanical characteristics of this induced membrane in order (i) to optimize the biomaterial constituting the spacer, (ii) to analyze the optimal duration between the two operative times, and (iii) to evaluate the contribution of bone tissue engineered products as a filling material. This study is conducted in collaboration with Professor T. Bégué.

3/ Degenerative knee pathology

Pain and swelling are typical symptoms of cartilage damages or degenerative meniscus injuries. The roles of the menisci, acting as shock absorbers, and that of the synovial fluid, acting as a lubricant, are critical for the proper functioning of the knee joint, and these two tissues need to be further characterized at the cellular and mechanical levels, in order to better understand their alteration, which is a source of premature ageing. The objective of the present project is to adapt recent, biophysical techniques for surface analysis to the characterization of synovial fluid and menisci, both healthy and pathological, in a clinical and prognostic vision. The stakes of this study are real because its results would greatly help to improve meniscus prostheses, currently still in the experimental clinical stage. This study is conducted in collaboration with Professor D. Biau.

Publications of the projects

Bachy, M., Sherifi, I., Zadegan, F., Petite, H., Vialle, R., Hannouche, D. Allograft integration in a rabbit transgenic model for anterior cruciate ligament reconstruction (2016) Orthopaedics and Traumatology: Surgery and Research, 102 (2), pp. 189-195.  Link for the publication .

Aurégan, J.-C., Bégué, T., Rigoulot, G., Glorion, C., Pannier, S. Success rate and risk factors of failure of the induced membrane technique in children: a systematic review (2016) Injury, 47, pp. 62-67.  Link for the publication .

Imbert L, Aurégan J-C, Pernelle K, Hoc T. Mechanical and mineral properties of osteogenesis imperfecta human bones at the tissue level (2014) Bone, 65, pp.18-24. Link for the publication .