Therapy – Our Method for Success
A cure is only possible through radical surgical removal of the necrotic bone tissue, including the adhering germs. A surgical debridement clearly creates an empty space. This so-called dead space represents a weak link in many ways: first of all mechanically, but also as a nucleus for reinfection. So it has to be filled – but with what? Any material that is not supplied with blood will immediately become recolonized by bacteria and thus maintains the infection. This also applies to bone grafts, which of course would be the best replacement, because they can restore the bone structure and provide immediate mechanical strength. Bone grafts are therefore usually not carried out until several weeks after successful debridement, when all signs of infection have disappeared.
How is it done?
The so-called debridement is conducted the same way as it has been previously in accordance with the rules of septic surgery. Foreign materials, dead tissue and infected bone with poor circulation are radically removed. After complete debridement the affected area is cleaned with a high-pressure cleaning lavage.
Boundary surfaces of healthy bone are freshened with a high speed milling machine. Subsequently, impregnated bone grafts are used to fill the prepared bed. In most cases these are used in the form of granules, for they allow for accurate replication of the original structures. Preformed complete "spare parts" are also available if needed. Since the grafts ensure high local antibiotic levels in the surgical area over the following weeks, simultaneous stabilization with metallic implants or artificial joints is easily possible.
At Döbling Osteitis Center we pay close attention to the choice of materials used - bone cement is avoided in any case. After the reconstruction is complete a drainage is inserted (usually for 2 to 3 days) and the wound closed immediately. All patients will be immediately mobilized and treated with physiotherapy according to their individual circumstances and needs. Partial loading is almost always immediately possible, full loading depending on the type and extent of the surgical procedure.
What substance is used to fill the missing bone space?
In a long series of tests, Dr. Winkler has found a method to impregnate bone tissue with high doses of antibiotics. There are two ways of antibiotic impregnation which have proven to be ideal: vancomycin ("V") and tobramycin ("T").
- Vancomycin for infections with Gram-positive bacteria used (e.g., all types of staphylococci, including MRSA).
- Tobramycin is used in gram-negative pathogens.
Dr. Winkler uses bone from organ donors, so-called allograft, which is highly purified of all antigenic components and therefore not rejected by the recipient. Since the "scaffolding" of bone, consisting of remains of collagen and minerals, is preserved in the process, allograft exhibits almost the same carrying capacity as natural bone and can be converted by the body into live endogenous bone.
Thus, our method offers two fundamental advantages:
- The antibiotic concentrations achieved are significantly higher than for all other methods and are located directly at the site of infection, for the first time making also the elimination of biofilm remains possible.
- Since donor bone is used, no additional surgery on the patient is required, e.g. to remove antibiotic bead chains or to harvest the patient's own cancellous bone (e.g. from the pelvis).
Often osteomyelitis is not the only problem, but is complicated by disorders of fracture healing or very large defects. Thanks to our method, simultaneous fixation by implanting titanium elements is possible even in unstable conditions ("nonunion").
- Hip replacement: Rationale for one stage exchange of infected hip replacement using uncemented implants and antibiotic impregnated bone graft
- Discussion in the United States: More work required to prevent and successfully treat periprosthetic infection