Antibiotic Beads Research Articles

Outcome of Transmetatarsal Amputations in Diabetics Using Antibiotic Beads

Diabetic patients with transmetatarsal amputation (TMA) for chronic forefoot ulceration or necrosis are at high risk for postoperative skin breakdown and subsequent amputation. Locally applied antibiotics may reduce the revision rate and improve the outcome. In a retrospective comparative study, 60 diabetic patients (65 feet) with forefoot ulceration or necrosis were treated with TMA by three surgeons in three hospitals. In the "beads group'' (46 patients, 49 feet) TMA was combined with local application of bioabsorbable, tobramycin impregnated calcium sulphate beads (OsteoSet-T beads, Wright Medical, Memphis, TN) as a single-stage procedure. The remaining 16 patients had transmetatarsal amputation without beads at the surgeon's discretion and acted as a control group. For all patients, time to healing, length of hospital stay, number of revisions for wound breakdown and conversions to a higher-level amputation were retrospectively reviewed. Of the 60 patients 17 had died and three were lost to followup, leaving 40 patients available for latest followup at 29 months. The Foot & Ankle Outcome Score, Foot Function index, SF-36, and Comorbidity score were recorded. The revision rate for wound breakdown after TMA was 8.2% (4/49) in the beads group, and 25% (4/16) in the control group (p<0.05). At latest followup, 27% (13/49) in the beads group, and 25% (4/16) in the control group had to be converted to transtibial amputation. Patients in the beads group scored worse for activities of daily living in the FAOS and SF-36 (p < 0.05), and demonstrated more health problems in the Comorbidity scores (not significant), indicating sicker individuals in the beads group. Bioabsorbable calcium sulphate antibiotic beads may be a useful addition for TMA for patients with non-healing diabetic ulcerations of the forefoot. The single-stage procedure could have a significant impact on the management of diabetic forefoot ulcerations by preventing additional hospital stays, improving the patient's quality of life and minimizing cost.

Use of antibiotic beads in treating chronic osteomyelitis

Background and Objectives: Chronic osteomyelitis results when bone tissue dies as a result of the lost blood supply. Usual management includes sequestrectomy and administration of high doses of antibiotics, but this can be difficult because of the limited circulation and poor penetration of antimicrobial agents into the site. Inherent undesirable side effects may also render systemic antibiotic treatment inadvisable. Osteomyelitis of the maxillofacial skeleton may not be very common in the developed countries but incidences are high in developing countries. But regardless of the country of origin, there is a select groups of patients who have an increased risk of developing osteomyelitis: specifically those who have undergone radiotherapy affecting the mandible (which may result in a specific form of osteomyelitis termed osteoradionecrosis), and the immunocompromised, including uncontrolled diabetics, and patients on immunosuppressive therapy, making systemic treatment of high dose antibiotics more complicated. In developing countries, chronic osteomyelitis often results from untreated acute haematogenous osteomyelitis. This study aims to present a good alternative for difficult chronic and refractory cases in the form of polymethyl methacrylate beads impregnated with antibiotics.

An evaluation of the shelf life of ceftriaxone–polymethylmethacrylate antibiotic beads

Background In a resource poor country like ours, left-over ceftriaxone-impregnated beads produced intraoperatively for treating chronic osteomyelitis need not be wasted. The possibility of keeping them on the shelf for use for indigent patients and also in the treatment of open fractures that often present late in our environment was considered. Thus, it became necessary to evaluate the shelf life of these antibiotic beads when stored as dry or wet beads at tropical room temperature.

Prosthesis Retention, Serial Debridement, and Antibiotic Bead Use for the Treatment of Infection Following Total Joint Arthroplasty

The clinical outcomes of a consecutive series of deep total joint infections treated with a prosthesis retaining protocol were reviewed. Each patient underwent surgical treatment consisting of serial irrigation and debridements, polyethylene exchange when applicable, interval placement and exchange of intra-articular tobramycin/vancomycin-impregnated polymethylmethacrylate beads and 6 weeks of intravenous antibiotics. The primary outcome measures were clinical, radiographic, or laboratory evidence of recurrent prosthetic infection or revision total joint arthroplasty for any reason. At a mean follow-up of 37 months (range, 23-41 months), all infections were eradicated while retaining prosthetic components. No further operative intervention was required for any patient. This treatment protocol can be successful in appropriately selected patients, presenting with early postoperative or acute hematogenous deep total joint infections.

Treatment of Long Bone Osteomyelitis With a Mechanically Stable Intramedullar Antibiotic Dispenser: Nineteen Consecutive Cases With a Minimum of 12 Months Follow-Up

Antibiotic cement beads are the most common system of local antibiotic delivery. Unfortunately, bead strings do not give mechanical support to the fracture site, stability being fundamental in osteomyelitis treatment. Local treatment associated with bone stability should improve the results in posttraumatic osteomyelitis. The objective of this article is to present our experience in the treatment of long bone osteomyelitis using an intramedullary, mechanically stable antibiotic dispenser. We present a retrospective review of a consecutive series of patients with a long bone osteomyelitis treated using an intramedullary, mechanically stable antibiotic dispenser. The dispenser used with a T-95 chest tube filled with poly(methyl methacrylate) + antibiotic (vancomycin, gentamycin, or both, tobramycin or imipenem; depending on culture results) and with a metal center (Ender nail). Fifteen patients were men and three were women, with an average age of 37 years (range, 18-52 years). In four cases, treatment involved the femur and in 15 the tibia. Positive cultures were obtained from each patient. Methicillin-resistant Staphylococcus aureus was isolated in 17 cases. The intramedullary dispenser was removed between 6 and 76 weeks after surgery. Success was defined as negative cultures after dispenser removal. Follow-up period was between 10 and 54 months. Negative cultures were obtained from intramedullary reaming after dispenser removal in all but one patient who could not finish treatment because of local intolerance to antibiotic treatment. None of the 17 patients presented an infection recurrence. The combination of local antibiotic treatment with bone segment stability showed acceptable results in our short series of patients. Further investigation on locked intramedullary antibiotic dispensers providing improved stability will help us learn about this difficult clinical scenario.

Evolving Microbiology and Treatment of Extracavitary Prosthetic Graft Infections

The authors report the microbiology and outcomes following an individualized treatment algorithm for extracavitary (EC) prosthetic graft infection, including the use of graft preservation and in situ graft replacement techniques. A retrospective 8-year review of 87 patients treated for EC prosthetic graft infections was carried out. The treatment algorithm included culture-specific antibiotic therapy, surgical site debridement with antibiotic bead placement, selected graft preservation with muscle flap coverage, or graft excision with in situ conduit replacement. Outcomes measured included death, limb loss, and recurrent infection. It was found that present-day management of EC prosthetic graft infections is associated with lower mortality and morbidity despite changes in microbiology and the increased application of graft preservation and in situ grafting treatments.

Management of Medullary Osteomyelitis of the Humerus

Osteomyelitis is a severe infection of bone and is particularly challenging to treat when involving long bones. Osteomyelitis of the humerus is an uncommon but difficult problem, and the guidelines of treatment have been drawn from the literature on the treatment of tibial and femoral osteomyelitis. We present our technique for treating adult hematogenous medullary osteomyelitis of the humerus. Steps include the following: (1) a deltopectoral approach to the humerus, (2) formation of a cortical window in the proximal humerus, (3) biopsy and reaming of the intramedullary canal from proximal to distal under fluoroscopy, (4) lavage of the intramedullary canal, (5) placement of antibiotic-impregnated antibiotic beads on a stainless steel wire into the canal, and (6) long-term antibiotics and laboratory monitoring of white blood cell count and erythrocyte sedimentation rates levels. Preliminary clinical results with at least 12 months' follow-up have resulted in excellent results without complications. We recommend this technique for the treatment of osteomyelitis of the humerus, for it affords a reliable and familiar approach to the treatment of a difficult infection of the humerus.

Regional Antibiotic Delivery for the Treatment of Experimental Prosthetic Graft Infections

To evaluate the efficacy of antibiotic-impregnated polymethylmethacrylate (PMMA) beads in eradication of an arterial prosthetic graft methicillin-resistant Staphylococcus aureus (MRSA) biofilm in an experimental animal model. Forty rats underwent subcutaneous implantation of a MRSA-colonized arterial polytetrafluoroethylene (PTFE) 1 x 1 cm wafer on the back. The effect of regional antibiosis produced by antibiotic PMMA bead placement adjacent to the infected PTFE wafer was determined using four 10-animal study groups: control (no antibiotic), PMMA bead with no antibiotic, PMMA bead with 10% vancomycin, and PMMA bead with 10% daptomycin. After 3 d, the PTFE wafers were explanted and quantitative biofilm cultures, expressed as colony-forming units (CFU) per graft wafer, performed using real-time polymerase chain reaction to assess MRSA eradication. No systemic antibiotic was administered. Bioassays of antibiotic bead bacteriocidal were performed by measuring zone of inhibition diameters on MRSA colonized agar culture plates prior to and following graft explantation. All animal tolerated implantation of the MRSA-infected PTFE wafer and survived the 3 d until graft explantation. Quantitative biofilm cultures demonstrated a significant decrease (P < 0.01) in MRSA CFUs present on the PTFE wafer surfaces in the presence of both the vancomycin- and daptomycin-impregnated beads compared to controls and plain PMMA beads. Both vancomycin and daptomycin PMMA beads retained antibacterial activity after 3 d of implantation with decrease in zones of inhibition of 15% and 45%, respectively. Regional antibiotic delivery using an antibiotic-impregnated PMMA bead reduced the bacterial biofilm concentration in experimental subcutaneous pocket model of vascular surgical site infection. The delivery of antibiotics via a PMMA bead may be a useful adjunct in the treatment of vascular surgical site infection.

Delayed Femoral Shaft Fracture Secondary to Nail Gun Injury: A Case Report

Nail gun injuries are common workplace occurrences among construction workers; however, delayed fractures of the femur after a nail gun injury are not found in the medical literature. We report the case of a patient who presented with such a fracture 3 days after accidentally firing a nail into his thigh. The patient was taken to the operating room for intramedullary nailing, irrigation and debridement, and antibiotic beads. Standard postoperative hospital care was provided, and after 2 days of intravenous antibiotics, the patient was returned to the operating room for removal of the antibiotic beads and a delayed primary closure. At the most recent follow-up, over 1 year postinjury, he had radiographic healing and was asymptomatic. Although it is difficult to predict whether the stress riser created by a nail gun injury will lead to a fracture, weight-bearing status and the aggressiveness of treatment to prevent infection are factors that need to be carefully considered in patients with this type of injury.

Treatment Protocol for Open AO/OTA Type C3 Pilon Fractures With Segmental Bone Loss

To evaluate the results in patients with open AO/OTA type C3 pilon fractures with segmental bone loss who were treated with a standard treatment protocol. Retrospective case series. Level I trauma center. Of 117 acute open type C pilon fractures treated during the study period, 10 patients with AO/OTA type C3 fractures and segmental metaphyseal bone loss were amenable to treatment with a standard protocol. All patients were treated with immediate debridement and external fixation (stage 1). After a delay of 1-3 weeks, patients with a healthy-appearing soft tissue envelope and no sign of infection underwent open reduction, plate fixation, and antibiotic bead placement (stage 2). Several months later, planned bone grafting was performed (stage 3). The complication rate, additional procedures, and time to bony union were determined. The treatment protocol was able to be completed in all 10 patients. No cases of acute infection or wound necrosis after plate fixation and antibiotic bead placement occurred. Two cases of late infection occurred after delayed bone grafting, one of which was successfully treated and the other resulted in amputation. Nine of the 10 patients healed at an average of 24 weeks. Limb salvage in the most severe open pilon fractures is difficult. In patients with benign soft tissues at several weeks after temporary external fixation, open reduction, antibiotic bead placement, and a delayed bone grafting procedure are associated with a low complication rate and predictable fracture healing.

Antibiotic Beads: Tips and Tricks Learned at a Busy County Hospital

This technique simplifies and improves the production of antibiotic beads in the operating room.

Antibiotic Beads: Tips and Tricks Learned at a Busy County Hospital

This technique simplifies and improves the production of antibiotic beads in the operating room.

Successful Bridge to Transplant in a Highly Sensitized Patient With a Complicated Pump Pocket Infection

A 32-year-old man with doxorubicin-induced cardiomyopathy presented in cardiogenic shock. He underwent placement of a Novacor (WorldHeart, Inc., Oakland, CA) left ventricular assist device as a bridge to transplant. Post-operatively he developed a pump pocket infection and dehiscence of his abdominal wound with exposure of the pump. This was treated with irrigation and drainage, antibiotic bead placement and flap closure. Both pre- and post-operative panel-reactive antibodies (PRA) were elevated. He underwent desensitization with intravenous immune globulin (IVIg), rituximab, mycophenolate mofetil and pre-operative plasmapheresis. A donor heart was identified and found to be acceptable by virtual crossmatch. He was transplanted and is doing well with normal graft function at >1 year post-operatively.

Papers Presented at the 2007 Meeting of the Musculoskeletal Infection Society: Editorial Comment

Surgical site infections (SSI) are the third most common nosocomial infection in the United States and are associated with substantial morbidity, mortality and expense. These infections account for 38% of the infections affecting the 27 million patients who undergo surgery each year. The Joint Commission has identified nosocomial infection rates as an indicator of quality care and a reliable measure of institutional quality assurance. In addition, an increasing number of health plans are now using cost-of-care data (SSI) to profile physicians for network selection. “Report cards” containing these profile results are posted on health plan Web sites with the intent to incentivize patients to seek care only from “profile-favorable” physicians. This has led the American public to believe surgical infections are potentially preventable (unless proven otherwise). In 2006, the Institute of Medicine report “Rewarding Provider Performance: Aligning Incentives in Medicare” (September 2006) recommended pay for performance (P4P) programs as an “immediate opportunity” to align incentives for performance improvement. Shortly thereafter, legislature required the Centers for Medicare & Medicaid Services (CMS) to adopt this approach for Medicare. Despite a system-wide concern over the choice and validity of measurements used to ascertain “improvement,” more than half of commercial health maintenance organizations currently have P4P systems in place. As the categories of providers (clinicians, hospitals, and other health care facilities), numbers of measures, and dollar amounts at risk have increased, we are to be held more accountable than ever before. This month, CORR features scientific papers presented at the 17th annual meeting of the Musculoskeletal Infection Society of North America held in San Diego, California. The theme of the congress was “The Prevention and Treatment of Surgical Site Infections.” The first six papers in this symposium address SSI prophylaxis: patient selection, asepsis, and perioperative wound monitoring. The molecular biology evidenced by FDG-PET Scans has been found useful in the differentiation of septic and aseptic prosthetic loosening. Two large, prospective, total joint series have documented a substantial decrease in surgical site infections following protocols to decolonize patients harboring virulent Staphylococcal pathogens in their anterior nares. Nosocomial colonization of one healthcare center was itself the source for an outbreak of infections caused by multidrug-resistant organisms in military wounds. Lastly, postoperative hematoma formation and persistent wound drainage have been correlated with an increase in SSI following total joint arthroplasty. Three papers were selected from the basic science forum on the topic of antibiotic delivery systems. McLaren et al. further clarify the release potential of hand-made, acylic, antibiotic beads. Then chitosan, made from the shells of crustaceans, has been introduced as a antibiotic-delivery vehicle due to its film-forming properties, biocompatibility and slow biodegradation. Until recently, the inability to incorporate certain drugs into biodegradable beads has limited the arsenal available for treating multidrug-resistant, Gram positive pathogens such as methacillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant Enterococcus (VRE); the authors of “Activity of Eluted Daptomycin from Calcium Sulfate Against Two Strains of Staphylococcus” disclose a clever method to incorporate daptomycin into calcium sulfate pellets using commercially available OsteoSet® kits. The last four papers link a timely diagnosis, appropriate treatment and predictable outcomes with new information regarding the natural history of specific musculoskeletal infections: septic arthritis of the ankle and the shoulder; polymicrobial prosthetic joint infections; and thigh pyomyositis. Segues of such “evidence” to newer, specific nuances of therapy shall further serve to justify our investigations with logical conclusions. We are being held responsible. Orthopaedic surgeons are under particular scrutiny: our operations are growing more and more complex; we are experiencing a higher incidence of patients compromised with significant comorbidities; the use of surgical implants is on the rise. The increased focus on quality measures, including the implementation of the Surgical Care Improvement Project, will soon bring discussions on musculoskeletal infection to the forefront. With the high cost of health care, increased patient awareness, escalating medico-legal issues and insurance pressures, the medical community must advocate patient safety and make every effort to support “best practices.”

An Unusual Case Report of Two Bone Osteomyelitis With Long-Term Follow-up

A 49 year-old patient, with a history of rheumatoid arthritis, presents with suspected septic arthritis of the ankle and subtalar joints. The patient was found to have osteomyelitis of both the talus and calcaneus. The patient was treated by debridement, antibiotic impregnated PMMA beads, and ultimately, a subtalar joint fusion. This case illustrates the importance of the early recognition and diagnosis, the possible sequelae, and the need for aggressive treatment of a septic joint.

Treatment of chronic femoral osteomyelitis with platelet-rich plasma (PRP): A case report

Chronic osteomyelitis is a serious problem in developing countries. A lot of patients with chronic osteomyelitis have to be treated for a very long period and get several operations including complete debridement, antibiotic bead implant, bone grafts, etc. However, traditional methods seem to be ineffective in some patients, who always have a high incidence of recurrence. We report a case of chronic osteomyelitis in bilateral femurs, which has been treated with long time antibiotic therapy, about twenty debridements, yet the sinus remained unhealed for over four years. At the end of this period, we used PRP to treat the unhealed sinus and obtained good results. Though the mechanism by which PRP treats chronic osteomyelitis is now unclear, the results encourage study further.

The Vascularized Medial Femoral Condyle Periosteal Bone Flap for the Treatment of Recalcitrant Bony Nonunions

The purpose of this study was to examine our experience with this flap for the treatment of recalcitrant nonunions of the extremities. A retrospective chart review was performed on 11 consecutive patients treated with the medial femoral periosteal bone flap from June 2003 to March 2005. Patient demographics, nonunion characteristics, complications, and long-term outcome based on radiographic and clinical parameters were analyzed. Nine free transfers and 3 pedicled flaps were used for a total of 12 nonunion sites in 11 patients. The average age of the patient population was 49 years (21-64 years). The location of the nonunion sites were femur (n = 4), tibia (n = 2), humerus (n = 3), clavicle (n = 2), and radius (n = 1). The nonunion sites were secondary to traumatic fractures complicated by osteomyelitis (n = 10) and tumor extirpation (n = 2). The time period of nonunion prior to the use of vascularized periosteal bone graft ranged from 10 months to 23 years (median = 23 months). All patients had previous attempts at debridement with or without antibiotic bead placement, and all underwent rigid fixation with or without nonvascularized bone grafts prior to vascularized grafting. Following flap placement, 9 (75%) of the nonunion sites healed primarily without complication at an average period of 3.8 months (2-7 months). Two nonunions healed secondarily following hardware modification. There was only 1 flap failure secondary to arterial thrombosis, resulting in a below-knee amputation. The rate of limb salvage was 91%. Donor-site morbidity was minimal, with postoperative seromas occurring in 3 patients.

Does Antibiotic Elution From PMMA Beads Deteriorate after 1-year Shelf Storage?

Antibiotic-impregnated polymethylmethacrylate beads are widely used as an adjunct in the treatment of orthopaedic infections. Because there is no commercially available bead in the United States, surgeons must manufacture bead sets at the time of implantation. This can be time consuming and wasteful. We hypothesized antibiotic-impregnated beads would maintain consistent elution for up to 1 year after manufacturing and storage. Tobramycin-impregnated antibiotic beads were manufactured using a bead mold. The antibiotic was either hand-mixed into the polymethylmethacrylate powder (1.2 g/40 g) or came premixed from the factory (1 g/40 g). Packages of beads were gas-sterilized and stored at room temperature. Beads were tested at 0, 1, 2, 3, 6, and 12 months. Antibiotic levels in the eluent from each day of the month were measured. We were unable to detect any difference in the amount of antibiotic elution between beads tested immediately after manufacture and beads manufactured and stored for 6 or 12 months. Beads with hand-mixed antibiotics eluted higher levels of antibiotics than the beads prepared with factory-mixed antibiotics. We conclude antibiotic beads can be made, sterilized, and used after 1 year of storage with no deleterious effect on antibiotic elution characteristics.

Use of Implantable Bone Growth Stimulation in Charcot Ankle Arthrodesis

The purpose of this study was to review the results of arthrodesis of the Charcot hindfoot when an implantable bone growth stimulator was added to the procedure. Arthrodesis of the Charcot hindfoot has a high nonunion and complication rate. Ten patients (ages 50 to 69 years) with Charcot neuroarthropathy of the ankle, hindfoot, or both had arthrodesis with use of rigid internal fixation and an implantable bone growth stimulator. There were six tibiotalocalcaneal, two pantalar, and two tibiocalcaneal arthrodeses. An intramedullary nail was used in nine patients and a blade plate was used in one patient. All but one patient was diabetic. Four of the ten patients had preoperative osteomyelitis or postoperative infection. Another patient had purulent drainage, although cultures were negative. Four patients had a preoperative ulceration. Five patients had a two-stage procedure for debridement of infected bone, removal of hardware, and placement of antibiotic beads. Autogenous bone graft from the distal fibula or proximal tibia was used in all patients. One patient with a preoperative osteomyelitis developed a stable ankle pseudarthrosis. The other nine patients fused at an average of 3.7 months after surgery for a fusion rate of 90%. There were two major complications and eight minor complications. There were no amputations. All patients were ambulatory in a double upright brace or shoes for diabetic patients and were free of ulceration at the time of followup. Average American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot score improved from 21 preoperatively to 59 postoperatively. The adjunctive use of an implantable bone growth stimulator in conjunction with rigid internal fixation, autogenous bone grafting, and sound operative technique may enhance the outcome and fusion rate in patients undergoing arthrodesis for Charcot neuroarthropathy of the ankle and hindfoot.

External fixation of tibial pilon fractures and fracture healing

Distal tibial fractures are rare and difficult to treat because the bones are subcutaneous. External fixation is commonly used, but the method often results in delayed union. The aim of the present study was to find out the factors that affect fracture union in tibial pilon fractures. For this purpose, prospective data collection of tibial pilon fractures was carried out in 1998-2004, resulting in 159 fractures, of which 83 were treated with external fixation. Additionally, 23 open tibial fractures with significant > 3 cm bone defect that were treated with a staged method in 2000-2004 were retrospectively evaluated. The specific questions to be answered were: What are the risk factors for delayed union associated with two-ring hybrid external fixation? Does human recombinant BMP-7 accelerate healing? What is the role of temporary ankle-spanning external fixation? What is the healing potential of distal tibial bone loss treated with a staged method using antibiotic beads and subsequent autogenous cancellous grafting compared to other locations of the tibia? The following risk factors for delayed healing after external fixation were identified: post-reduction fracture gap of >3 mm and fixation of the associated fibula fracture. Fracture displacement could be better controlled with initial temporary external fixation than with early definitive fixation, but it had no significant effect on healing time, functional outcome or complication rate. Osteoinduction with rhBMP-7 was found to accelerate fracture healing and to shorten the sick leave. A staged method using antibiotic beads and subsequent autogenous cancellous grafting proved to be effective in the treatment of tibial bone loss. Healing potential of the bone loss in distal tibia was at least equally good as in other locations of the tibia.