What this Trial Is About

Chronic osteomyelitis is a serious osteoarticular infection that most often occurs in the long bones (tibia, femur, humerus), responsible for significant morbidity with risk of fracture and amputation. It is due to the presence of bacteria in the bone marrow, sometimes responsible for an intraosseous abscess. Chronic osteomyelitis can have a hematogenous or more often exogenous origin, after trauma or surgery. The bacteria involved have the ability to modify their metabolism and involve persistence mechanisms (such as biofilm) making them difficult to eradicate. The treatment of chronic osteomyelitis requires surgery, i.e. corticotomy, which means opening of the bone cortex to perform an endomedullary curettage to identify the bacteria, remove any sequestration (bone fragments to which the bacteria adhere as biofilm) and reduce the bacterial inoculum. At the same time, or at a second stage, a skin and soft tissue/muscle flap may be required, especially in patients with long-standing disease with embrittlement and adhesion of the skin and soft tissue to the underlying bone. Post-operatively, the patient receives a probabilistic systemic antibiotic therapy and then a systemic antibiotic therapy targeted on the identified germ, for a period of 3 months. The effectiveness of these antibiotics is based on their ability to penetrate bone tissue. Despite the progress made in both antibiotics and surgical treatments, the probability of failure (recurrence of infection) is around 20%, and has unfortunately remained stable for more than 20 years. Cerament-G (BONESUPPORT AB Laboratory, Sweden), a synthetic bone substitute composed of hydroxyapatite, calcium sulphate, and gentamicin, fills the "dead space" formed during surgery, prevents infection of this blood-filled cavity, and promotes bone regeneration within this space (limiting the risk of fracture in the medium and long term). Cerament-G also delivers locally very high doses of gentamicin (concentration of 17.5 mg/mL in the device) for several weeks. Gentamicine is a broad-spectrum bactericidal antibiotic effective against the vast majority of bacteria involved in osteoarticular infections. It provides effective local antibiotic therapy through wide exposure and prolonged concentrations during several weeks. To date, there is no other bone substitute with antibiotics available in France. Two prospective studies have shown that Cerament-G reduces the number of infectious recurrences (about 5%). This innovation is available in France but at a high price (between 2,500 and 4,000 euros) and is not currently reimbursed. However, the use of this product would make it possible to improve the health and quality of life of patients while avoiding certain consumption of resources.

Evaluation of the Efficiency of the Bone Substitute Cerament-G Locally Delivering Gentamicin in the Treatment of Chronic Osteomyelitis of Long Bones