Increased oxacillin resistance in thigh pyomyositis in diabetic patients.

UNLABELLED: Thigh abscesses due to pyomyositis are uncommon. To guide empiric antibiotic therapy in diabetics we determined the rate of such infections due to oxacillin-resistant Staphylococcus aureus and Gram-negative organism infections, and whether the occurrence of oxacillin-resistant pathogens increased during the study period. We retrospectively reviewed 39 adult patients with diabetes mellitus treated for a deep thigh abscess. There were 29 men and 10 women; their mean age was 45 years. Comorbidities were present in 15 patients. S. aureus was the most common pathogen, present in 82% (32/39) of our patients. Gram-negative organisms were cultured in 14% (6/39) of patients and anaerobes in 10% (4/39). The infection was polymicrobial in 12 of 39 patients (31%). Oxacillin-resistant S. aureus comprised 25% (8/32) of infections due to S. aureus. Oxacillin-resistance increased during the last 3 years of this study from one of 18 S. aureus isolates from 1994 to 2004 to seven of 14 isolates from 2004 to 2006. In diabetic patients with thigh pyomyositis, empiric antibiotic therapy should provide broad spectrum coverage for oxacillin-resistant S. aureus, Gram-negative, as well as anaerobic organisms. LEVEL OF EVIDENCE: Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Culture results and amputation rates in high-pressure paint gun injuries of the hand.

High-pressure paint gun injuries have been well described in the literature, and the use of antibiotics is recommended as part of their management. However, there is no scientific evidence to support the use of antibiotics. In addition, the type of paint injected (water- versus oil-based) has never been investigated to determine the extent of morbidity resulting from these injuries. This study examines the organisms cultured in wounds resulting from these injuries and whether the type of paint injected had an influence on amputation rates. Charts of 35 patients with high-pressure paint gun injuries to their hands were reviewed. The amputation rate was 50% with oil-based paints and 0% with water-based paints. Forty-seven percent of wound cultures were positive, with gram-negative bacteria found in 58% of isolates. Our findings support the use of antibiotics, which should cover both gram-positive and gram-negative organisms.

Mucormycosis of the tibia: a case report and review of the literature.

Mucormycosis is an uncommon but highly aggressive fungal infection most commonly occurring in hosts who are immunologically predisposed to infection. Only seven previously documented cases of tibial osteomyelitis attributable to Mucorales infection exist in the literature. An unusual case is reported of mucormycosis osteomyelitis developing in a patient who was immunocompromised after routine tibial Steinmann pin placement for the application of traction. Surgical debridement and amphotericin B were not sufficient to control the infection, and the patient subsequently underwent above-knee amputation. To the authors' knowledge this is the first description of mucormycosis causing osteomyelitis as a result of Steinmann pin tract infection.

Inhibitory effects of the quinolone antibiotics trovafloxacin, ciprofloxacin, and levofloxacin on osteoblastic cells in vitro.

We studied the inhibitory effects of the fluoroquinolones levofloxacin, ciprofloxacin, and trovafloxacin on growth and extracellular matrix mineralization in MC3T3-E1 osteoblast-like cell cultures. Levofloxacin had the least inhibitory effect on cell growth, with a 50% inhibitory concentration of approximately 80 microg/ml at 48 and 72 hours. Ciprofloxacin had an intermediate degree of inhibition, with a 50% inhibitory concentration of 40 microg/ml at 48 and 72 hours. Trovafloxacin exerted a profound inhibitory effect on cell growth, with a 50% inhibitory concentration of 0.5 microg/ml, lower than clinically achievable serum levels. The decreased cell counts with up to 2.5 microg/ml of trovafloxacin and with up to 40 microg/ml of ciprofloxacin were not associated with decreased rates of 5-bromo-2'-deoxyuridine incorporation per cell. Alatrovafloxacin, the L-alanyl-l-alanine prodrug of trovafloxacin, exerted effects on proliferation and 5-bromo-2'-deoxyuridine incorporation similar to those of the parent compound. The quinolones evaluated also inhibited extracellular matrix mineralization by MC3T3-E1 cells. Treatment of confluent cultures with trovafloxacin, ciprofloxacin, or levofloxacin resulted in strong inhibition of calcium deposition, as determined on day 14 by alizarin red staining and biochemical analysis. The effect was apparent with 2.5-5 microg/ml of each of the three antibiotics tested and progressively increased to more than a 90% decline in the calcium/protein ratio with 20-40 microg/ml antibiotic concentration. Further in vivo studies are advocated to evaluate the relevance of the in vitro cytotoxicity reported here to bone healing in orthopaedic patients.

Management of chronic deep infection following rotator cuff repair.

BACKGROUND: Deep infection of the shoulder following rotator cuff repair is uncommon. There are few reports in the literature regarding the management of such infections. METHODS: We retrospectively reviewed the charts of thirteen patients and recorded the demographic data, clinical and laboratory findings, risk factors, bacteriological findings, and results of surgical management. RESULTS: The average age of the patients was 63.7 years. The interval between the rotator cuff repair and the referral because of infection averaged 9.7 months. An average of 2.4 procedures were performed prior to referral because of infection, and an average of 2.1 procedures were performed at our institution. All patients had pain on presentation, and most had a restricted range of motion. Most patients were afebrile and did not have an elevated white blood-cell count but did have an elevated erythrocyte sedimentation rate. The most common organisms were Staphylococcus epidermidis, Staphylococcus aureus, and Propionibacterium species. At an average of 3.1 years, all patients were free of infection. Using the Simple Shoulder Test, eight patients stated that the shoulder was comfortable with the arm at rest by the side, they could sleep comfortably, and they were able to perform activities below shoulder level. However, most patients had poor overhead function. CONCLUSIONS: Extensive soft-tissue loss or destruction is associated with a worse prognosis. Extensive débridement, often combined with a muscle transfer, and administration of the appropriate antibiotics controlled the infection, although most patients were left with a substantial deficit in overhead function of the shoulder.

Limb salvage for chronic tibial osteomyelitis: an outcomes study.

BACKGROUND: The decision to undergo a limb salvage procedure is difficult and multifaceted. This study reviews the outcomes of patients with chronic tibial osteomyelitis who underwent limb salvage and hopes to enhance our understanding of the impact this complex procedure has on the patient's ability to have a functional and fulfilling life. METHODS: Forty-six patients, with at least 18 months follow-up, who had undergone limb salvage for chronic, refractory tibial osteomyelitis were evaluated. A modification of the Limb Extremity Outcomes Instrument was utilized emphasizing inquiries pertaining to quality of life. RESULTS: Thirty-nine (85%) of the 46 patients were able to ambulate independently without pain. All patients younger than 45 years of age had successful outcomes. Thirty-one percent of the patients with a positive smoking history were failures, and 71% of all failures were smokers. CONCLUSION: Limb salvage seems to be a satisfactory option for patients with chronic tibial osteomyelitis. A history of smoking and advanced age may have adverse affects and are relative contraindications.

The incidence of joint involvement with adjacent osteomyelitis in pediatric patients.

Sixty-six patients admitted to our institution over an 8-year period with the diagnosis of osteomyelitis were analyzed to determine the incidence of adjacent joint involvement. Patients with osteomyelitis of the hand, foot, spine, and extraarticular pelvis were excluded from this study. The average age was 5.8 years (range, 1 month to 17 years). Forty-two percent of our patients who had osteomyelitis had evidence of adjacent joint involvement (either septic or nonseptic). One third of our patients had evidence of septic joint involvement. The most commonly involved joint was the knee. There was no difference in the incidence of adjacent joint involvement in those patients who were younger than 18 months compared with the incidence in older children. Our study suggests that the incidence of adjacent joint involvement in children who have osteomyelitis is higher than that suggested in the literature. We believe that careful evaluation of the adjacent joint should be an important part of the evaluation of any child who has osteomyelitis.

Prospective, randomized, double-blind study comparing single-agent antibiotic therapy, ciprofloxacin, to combination antibiotic therapy in open fracture wounds.

OBJECTIVE: The purpose of this study was to compare the efficacy of a single agent, ciprofloxacin, with that of combination antibiotic therapy consisting of cefamandole and gentamicin in all types of open fracture wounds. STUDY DESIGN: A prospective double-blind randomized clinical trial. SETTING: A Level 1 trauma center. PATIENTS: One hundred ninety-five consecutive patients with 203 open fractures were enrolled over a twenty-month period. Twenty-nine fractures from low-velocity gunshot wounds were excluded, and three other patients were excluded because of protocol violations. Our final number of patients were 163, with 171 open fractures. MAIN OUTCOME MEASUREMENT: The infection rates for Type I and Type II open fractures for both antibiotic groups were calculated. The infection rate of Type III open fractures for both antibiotic groups was also calculated. Chi-square analysis with Yates correction was used to assess statistical significance of two treatment groups. RESULTS: The infection rate for Types I and II open fractures in the ciprofloxacin group was 5.8 percent and 6 percent for the cefamandole/gentamicin group (p = 1.000). The infection rate for Type III open fractures for the ciprofloxacin group was 31 percent (8 of 26) versus 7.7 percent (2 of 26) for the cefamandole/gentamicin group (p = 0.079). There were no statistically significant differences in infection rate between the group treated with ciprofloxacin and that treated with cefamandole/gentamicin for Types I and II open fracture wounds. However, there appeared to be a high failure rate for the ciprofloxacin Type III open fracture group, with patients being 5.33 times more likely to become infected than those in the combination therapy group. Although this difference was not statistically significant, possibly because of the small sample size, there was a definite trend toward statistical significance. CONCLUSION: Single-agent antibiotic therapy with ciprofloxacin is effective in treatment of Type I and Type II open fracture wounds. However, on the basis of our results, we cannot recommend ciprofloxacin alone for Type III wounds. Possibly one can use fluoroquinolones in combination therapy, specifically as an alternate to an aminoglycoside.

Sepsis and osteomyelitis about the ankle joint.

Sepsis and osteomyelitis about the ankle joint present a challenging clinical problem. Osteomyelitis usually follows open fracture of the distal tibia, often with a pilon fracture component. This article outlines the prevention of osteomyelitis in these difficult fractures. Treatment of subsequent osteomyelitis and sepsis, including the authors' experiences, is discussed. Septic ankle arthritis can occur hematogenously. In some patients, the optimal treatment for concomitant osteomyelitis and sepsis is a below knee amputation.

Culture results in open wound treatment with muscle transfer for tibial osteomyelitis.

Fifty-three patients who underwent a two-staged protocol of debridement and muscle flap coverage for chronic osteomyelitis of the tibia between 1991 and 1996 were evaluated. All patients underwent a thorough debridement of all nonviable tissue and bone at initial debridement. Multiple cultures were taken, including aerobic, anaerobic and fungal cultures from the pus, soft tissue, bone curettings and bone. All patients were treated with open wound management and dressing changes. Between 2 to 7 days, median 4 days, all patients underwent a second debridement with a complete set of identical cultures, and immediate soft tissue muscle transfer. There were 42 free vascularized and 11 local tissue transfers. The 53 patients were classified according to the Cierny-Mader classification for chronic osteomyelitis. Twenty-four patients had Stage IVA osteomyelitis, 10 patients had Stage IIIA osteomyelitis, nine patients had Stage IIIB osteomyelitis, eight patients had Stage IVB osteomyelitis, one patient had Stage IA osteomyelitis, and one patient had Stage IIB osteomyelitis. All 53 patients had positive cultures at the time of their initial debridement, and 14 of 53 (26%) had a positive culture at the time of the second debridement. Based on the results, it seems from a bacteriologic stand-point that the second debridement allows for the opportunity for redebridement and wound sterilization of organisms that still may be present.

Estimation of defect volume in segmental defects of the tibia and femur.

BACKGROUND: With the advent of modern limb salvage techniques, segmental bone loss in the lower extremity has become more common. METHODS: To aid preoperative planning when dealing with segmental bone loss in the femur and tibia, we performed a cadaveric study to estimate the volume of autogenous or allograft material required to fill defects located in various areas of the bones. RESULTS: The greatest volume was generally required in metaphyseal defects, with an average of 12 cc/cm in the distal femur and proximal tibia, 11 cc/cm in the proximal femur, and 6 cc/cm in the distal tibia. Diaphyseal defects were found to have the least variability with regard to the volume of graft material required for different specimens. Femoral diaphyseal defects required 7 cc/cm and tibial diaphyseal defects required 5 cc/cm. A slightly larger volume of allograft material was needed to fill all defects compared with autograft. CONCLUSION: This method allows one to estimate the amount of graft required for a defect of the femur and the tibia.

Local or free muscle flaps and unreamed interlocked nails for open tibial fractures.

The treatment of open tibial fractures associated with severe soft tissue injuries remains a difficult dilemma, even to the experienced fracture surgeon. To ascertain the efficacy of nailing tibial fractures with severe soft tissue injuries, a review of all open tibial fractures treated at the authors' institution was done. Those fractures initially stabilized with nonreamed nails which required muscle flaps for coverage were selected for study. Thirty-three patients (26 men, seven women) were treated with intramedullary nailing and muscle flap coverage for the soft tissue defects. The average length of followup was 12.1 months (range, 7-42 months). The average time to union was 27 weeks (range, 14-45 weeks). There were five (15%) infections: two (6%) superficial wound infections, one (3%) flap infection, and two (6%) cases of osteomyelitis. In no patient did the infection result in limb ablation. Thirteen of 33 (42%) patients required secondary procedures to enhance union. In this study, it was found that although delayed procedures frequently were required to promote fracture union, the time to union, and infection rates were not significantly different from those reported for external fixation of fractures that require local or free muscle transfers.

In vitro elution of tobramycin and vancomycin polymethylmethacrylate beads and spacers from Simplex and Palacos.

In vitro studies of antibiotic elution from polymethylmethacrylate cement comparing Simplex (Howmedica, Rutherford, NJ) with Palacos brands (Richards, Memphis, TN) have shown variable results. This study compares the elution of tobramycin and vancomycin from Simplex and Palacos beads and spacers. Six-millimeter beads and spacers were incubated in phosphate-buffered saline, and the solution was sampled and changed daily until the concentration of antibiotic fell below the minimum inhibitory concentration (MIC) for Staphylococcus aureus. In all groups, the Palacos PMMA beads and spacers showed elution at higher levels and remained above the MIC longer than did the Simplex PMMA beads. Tobramycin had superior elution to vancomycin in all groups. This in vitro study shows that Palacos PMMA has superior elution properties to Simplex PMMA in tobramycin and vancomycin beads and spacers.

Relation of surface area to in vitro elution characteristics of vancomycin-impregnated polymethylmethacrylate spacers.

To study the relationship between surface area and antibiotic elution from antibiotic-impregnated polymethylmethacrylate (PMMA) spacers, a standard block spacer made of vancomycin (4 g) and 40 g of PMMA was compared with two unique spacer designs, the "donut" and "fenestrated." The spacers were incubated in phosphate-buffered saline, which was changed daily, and a microbiologic assay was used to measure the antibiotic activity of the eluates. The donut and fenestrated spacers had 12% and 40% more surface area than the standard spacer, respectively. There was no significant difference, however, in daily elution levels of antibiotic between the donut spacer and the standard spacer. The fenestrated spacer displayed significantly better elution than either the standard or donut spacers, with an average of 20% more antibiotic eluted on any given day.

Infected total knee arthroplasty. Two-stage reimplantation with a gastrocnemius rotational flap.

This study reviews a consecutive series of 21 patients undergoing two-stage reimplantation total knee arthroplasty for late chronic infection. All 21 patients had late chronic infections, and 20 of 21 patients were compromised hosts. Seven different organisms were isolated at the time of prosthetic resection. Staphylococcus coagulase negative species was the most frequently isolated organism. At the time of reimplantation, a medial gastrocnemius rotational flap was rotated over the proximal tibia and knee for wound closure. The average explantation time was 25 weeks (range, 7-76 weeks), and no methylmethacrylate spacers were used. At an average 17-month followup (range, 5.1-33.1 months) all reimplanted total knee replacements remained in place with one patient having recurrent infection. At reimplantation, 11 patients had positive bacterial cultures from tissue specimens. Sixteen of the 33 (40%) positive cultures were from specimens taken from the medullary canal. At followup, the average Knee Society Score was 77.4 (range, 40-100). The lack of a methylmethacrylate spacer and a long explantation time were considered important factors in diminishing functional performance and determining the need for a gastrocnemius flap. A medial gastrocnemius rotational flap should be considered at the time of reimplantation total knee arthroplasty if the soft tissue envelope about the knee is compromised and cannot be closed without undue tension.

Salvage of the septic ankle with concomitant tibial osteomyelitis.

Five patients with concomitant distal tibia osteomyelitis and ankle sepsis with an open, draining wound were treated. All of the patients were men with an average age of 54.8 years. All of the bone infections were polymicrobial and had open draining wounds. A standardized protocol of radical soft tissue and bone debridement, soft tissue transfer, intravenous antibiotics, and delayed ankle fusion was employed. All five fusions were successful on first attempt, with an average time to fusion of 3.5 months. All patients were free of infection at an average follow-up of 27 months. We believe our aggressive treatment protocol can salvage these extremities and preclude amputation in properly selected cases.

Comparison of intravenous and oral antibiotic therapy in the treatment of fractures caused by low-velocity gunshots. A prospective, randomized study of infection rates.

One hundred and ninety consecutive patients (222 fractures) who had an extra-articular fracture of a long bone as a result of a low-velocity gunshot were randomized into two groups on the basis of the method of administration of antibiotics. Group 1 consisted of 101 patients (120 fractures) who were managed with intravenous administration of cephapirin sodium and gentamicin for three days. Group 2 comprised eighty-nine patients (102 fractures) who were managed with oral administration of ciprofloxacin for three days. The two groups were comparable in terms of the age of the patient, the locations of the fractures, and the time from the injury to the commencement of antibiotic therapy. Injuries that needed operative débridement or fixation were excluded. All patients were followed until the fracture had healed. Two infections developed in two of the ninety-nine patients (118 fractures) who completed the study in Group 1, and two infections developed in two of the eighty-seven patients (100 fractures) who completed the study in Group 2. With the numbers available, there was no significant difference in the rates of infection (2 per cent for both) between the two groups. All four fractures that were complicated by infection were located in the distal half of the tibia. We concluded that oral and intravenous administration of antibiotics were equally effective for prophylaxis against infection after an extra-articular fracture from a low-velocity gunshot.

Acute hematogenous osteomyelitis. An unusual cause of compartment syndrome in a child.

Acute compartment syndrome of the leg developed in a 4-year-old child due to acute hematogenous osteomyelitis of the proximal fibula. Because of its unusual presentation, the diagnosis of osteomyelitis initially was missed. This report suggests that the diagnosis of acute hematogenous osteomyelitis of the proximal part of the fibula should be considered in young children who present with acute compartment syndrome of the leg and who have no history of recent surgery or trauma.

Results of bone grafting for infected tibial nonunion.

Thirty-two patients with infected tibial nonunions were treated, including 24 men and 8 women whose ages ranged from 21 to 72 years (mean, 40 years). Thirty of 32 patients had bone defects < 3 cm. Using the Cierney-Mader classification of osteomyelitis, 11 of 32 (35%) patients were Stage 4A, and 21 of 32 (65%) patients were Stage 4B. All patients had irrigation, debridement, and stabilization using an external fixation device. Twenty-seven (84%) patients had muscle transfers. The time between initial debridement and muscle transfer ranged from 3 to 24 days (mean, 4 days). Bone grafting was performed between 6 weeks and 8 months (mean, 8 weeks) after soft tissue coverage. Patients received intravenous antibiotics for 2 to 6 weeks (mean, 6 weeks). Twenty patients received anterior grafting, 10 received posterolateral grafting, and 2 received both. Followup times ranged from 12 to 49 months (mean, 28 months). Twenty-nine of the 32 (91%) patients had tibial unions between 3 to 10 months (mean, 5.5 months) after bone grafting. The 3 failed tibias united after posterolateral grafting. Infection was controlled in all 32 patients. Autogenous cancellous bone grafting using infection control principles is an effective means to treat infected tibial nonunions.