Can The OsteoSet Lead To Better, Cost-Effective Healing?

Podiatrists are adding the OsteoSet Resorbable Mini-Bead Kit to their arsenal of treatments for osteomyelitis and diabetic foot infections. One prospective study reports that bone repair with the OsteoSet yielded a 98 percent success at 12 months for contained defects, according to the product’s manufacturer Wright Medical.1 For defects specifically caused by osteomyelitis, a different retrospective study reports a 64 percent healing rate.2 Those who have used the product in their practice have also seen favorable results. In the past year, Ritchard Rosen, DPM, says he has seen great outcomes in using the OsteoSet resorbable beads to treat diabetic infections and osteomyelitis. “To date, I have had complete healing of all wounds that have been impregnated with the OsteoSet beads,” says Dr. Rosen, a Fellow of the American College of Foot and Ankle Surgeons. “We have found the use of absorbable, antibiotic-impregnated calcium sulfate pellets a useful adjunct in some complex foot infections,” comments David G. Armstrong, DPM, Director of Research in the Podiatry Section of the Department of Surgery at the Southern Arizona VA Medical Center in Tuscon. How To Use The Product OsteoSet Resorbable Mini-Beads are available in standard and fast cure kits. The kit comes with a mold and Wright Medical says one side of it produces 200 3mm beads (5 cc) while the other side produces 50 4.8mm beads (5 cc). The company lists a five-step process for clinicians using the mini beads. To start, you would add OsteoSet Powder and diluent to a mixing bowl. After allowing it to sit, mix it thoroughly for 30 to 45 seconds until the consistency is paste-like. Using the spatula, apply an even coat of OsteoSet Paste to the supplied mold, completely filling each bead cavity. Tap the mold on a flat surface to remove the air bubbles. After again allowing the mold to sit, flex the mold to remove the beads and you’re ready to treat the patient. What Are The Key Advantages? Dr. Rosen notes that, in each case, he impregnates the beads with vancomycin to treat the infectious tissue. “Implanting the beads in soft tissue has demonstrated complete resorption of the beads over a two- to three-month time frame,” explains Dr. Rosen. In one case, he made the OsteoSet mixture into putty and implanted it into the body of the calcaneus to treat osteomyelitis. Dr. Rosen notes that calcium sulfate is osteoconductive when implanted in bone and he adds that you can see this on follow-up X-rays. For Dr. Rosen, the ideal implantable device should eliminate dead space, be biocompatible and totally resorbable. He says calcium sulfate qualifies on all counts and adds that the compound also allows you to incorporate water-soluble drugs into the matrix. Given this, Dr. Rosen says the OsteoSet’s advantages far outweigh the disadvantages. “The implantation of antibiotic beads in infectious tissue affords the patient high concentrations of antibiotic delivery to a specific site,” explains Dr. Rosen. Dr. Armstrong concurs, noting that this key benefit reduces the risk of potential complications. He also points out that the product’s resorbability gives it a potential edge over non-absorbable polymethylmethacrylate beads. A Cost-Effective Alternative To IV Antibiotics? If sufficient soft tissue is available, Dr. Rosen says you can close wounds as a single surgical procedure as opposed to doing a second incision in order to remove the non-absorbable implants such as PMMA. Extra capsular and extra osseous implantation fills the dead space and allows for tissue healing and intra-osseous implantation will cause osteoconduction, according to Dr. Rosen. He notes his patients are pleased with the OsteoSet results and the idea of presenting a surgical plan with the intent of one surgery vs. multiple surgeries is very appealing. Dr. Rosen adds: “Hopefully, this will decrease hospitalization time as well as the need for costly intravenous antibiotics for a lengthy course.” Addressing Possible Drainage Be aware that drainage is one potential complication of using the product. In the aforementioned prospective study, a multicenter clinical trial of long bone defects in 109 patients, reportedly 4 percent of the patients experienced drainage problems with the OsteoSet. According to Wright Medical, the study’s researchers concluded that drainage results from an osmotic effect caused by the presence of the pellets, and that the effect stops once the pellets dissolve. To this end, Dr. Rosen says he always advises his patients of the possible complications, alternatives and prognosis if he uses these beads. The study authors recommended using an active suction drain for 48 to 72 hours postoperatively, according to the company. Dr. Rosen believes copious drainage may be a learning curve issue as surgeons may initially implant too much volume of OsteoSet. “This causes large amounts of drainage and appears to be a problem,” notes Dr. Rosen. “This drainage is usually cultured for no bacterial growth and is, just that, excess OsteoSet. The learning curve will eventually let the surgeon not overload the wound, minimizing postoperative drainage.” Dr. Armstrong, a member of the American Diabetes Association’s National Board of Directors, also notes drainage as a primary disadvantage. He says he and his colleagues have found a significant amount of clear, serous discharge from the wounds as the calcium sulfate pellets hydrolyze in the wound. Wright Medical says any resulting serous drainage is not associated with purulence, wound erythema or discomfort for the patient. “While this is easily treated with an absorptive dressing, it is something that we anticipate and will deal with,” says Dr. Armstrong. “I should say, however, many of my colleagues who use this modality have not found this to be as significant as we have. We have also found that reducing/titrating the amount of pellets in the wound can help in reducing this problem.”
 

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References 1. Kelly CM, Wilkins RM, Gitelis S: The use of surgical grade calcium sulfate as a bone graft substitute, Clinical Orthopaedics and Related Research, January 2001. 2. Internal publication: A retrospective study of a bone graft substitute. Ref. SK 846-199; 1999. For further reading Armstrong DG, Findlow AH, Oyibo SO, Boulton AJ. The use of absorbable antibiotic-impregnated calcium sulphate pellets in the management of diabetic foot infections. Diabet Med. 2001 Nov;18(11):942-3.