VUV photoabsorption spectroscopy of sulfur dioxide ice.

In this paper we present the first study of the VUV photoabsorption spectrum of condensed phase SO(2) recorded over the VUV region 120 to 320 nm (10.33 to 3.64 eV). Distinct spectral features were observed that can be used to distinguish between the formation of amorphous and crystalline ice structures. These signatures may then be used to probe the formation of different ice structures as a function of both deposition rate and substrate temperature.

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.

Introduction to adult posttraumatic osteomyelitis of the tibia.

The tibia is the most frequent site of an open fracture, and treatment of adult posttraumatic osteomyelitis of the tibia represents a significant clinical problem that has been recognized for centuries. Ancient modalities such as immobilization and debridement are still mainstays of therapy, and recent developments such as the use of antibiotics and muscle transfer have helped to improve outcome. Osteomyelitis is classified based on the Cierny-Mader system to provide prognostic and therapeutic information. Open fractures can be classified by the Gustilo system, again providing prognostic and therapeutic data. Gustilo Type III fractures have a high likelihood of having infection develop. Treatment principles include immobilization, thorough debridement, control of infection through antibiotic use, control of dead space, and soft tissue coverage.

Early mycological treatment failure in AIDS-associated cryptococcal meningitis.

Cryptococcal meningitis causes significant morbidity and mortality in persons with AIDS. Of 236 AIDS patients treated with amphotericin B plus flucytosine, 29 (12%) died within 2 weeks and 62 (26%) died before 10 weeks. Just 129 (55%) of 236 patients were alive with negative cerebrospinal fluid (CSF) cultures at 10 weeks. Multivariate analyses identified that titer of cryptococcal antigen in CSF, serum albumin level, and CD4 cell count, together with dose of amphotericin B, had the strongest joint association with failure to achieve negative CSF cultures by day 14. Among patients with similar CSF cryptococcal antigen titers, CD4 cell counts, and serum albumin levels, the odds of failure at week 10 for those without negative CSF cultures by day 14 was five times that for those with negative CSF cultures by day 14 (odds ratio, 5.0; 95% confidence interval, 2.2-10.9). Prognosis is dismal for patients with AIDS-related cryptococcal meningitis. Multivariate analyses identified three components that, along with initial treatment, have the strongest joint association with early outcome. Clearly, more effective initial therapy and patient management strategies that address immune function and nutritional status are needed to improve outcomes of this disease.

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.

Delayed primary wound closure in upper extremity soft tissue infections.

Health care costs for inpatient care have been escalating. Homeless and indigent patients may be unable to have access to clean toilet facilities to perform adequate wound care. Evaluation of delayed primary closure of upper extremity soft tissue infections after incision and drainage in 34 patients was done. Patients were discharged at an average of 8.3 days (range, 5-21 days). This is 11 days less than the reported average granulation time for wounds to heal. No patient required readmission for surgery, wound care, or intravenous antibiotics. The authors' institution charges a rate of $2800 per patient day. A potential savings of $1,047,200 was realized.

Tissue pressures in pyogenic flexor tenosynovitis of the finger. Compartment syndrome and its management.

We investigated 14 patients with pyogenic flexor tenosynovitis for increased tissue pressures in involved digits. All showed raised pressures, in eight to 30 mmHg or more. These levels are consistent with a compartment syndrome. We describe the results of a modified operative technique which includes irrigation of the sheath and the leaving open of a lateral incision. This also allows early active mobilisation of the finger and has given satisfactory early results.

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.

Efficacy of immediate postirrigation culture in the treatment of upper-extremity abscesses.

A retrospective chart review of 192 patients of the musculoskeletal infection ward at the authors' facility was performed to assess the value of immediate postirrigation cultures in the treatment of acute soft tissue infections of the upper extremity. Twenty-two patients (11.5%) had postirrigation cultures with an organism that was not present in the preirrigation cultures. All of those organisms not previously found were gram-positive organisms, and no changes were necessary in the initial antibiotic regimes. Immediate postirrigation cultures did not prove to be effective in the information they provided related to treatment of acute soft tissue infections of the upper extremity.

Abscesses secondary to parenteral abuse of drugs. A study of demographic and bacteriological characteristics.

Seventy-seven patients (eighty-six lesions) who had been seen over a fifteen-month period because of an abscess at the site of injection due to parenteral abuse of drugs were identified in a retrospective review. Forty-one patients (forty-five abscesses) had had cultures before antibiotic therapy. Thirty (73 per cent) of the forty-one patients had isolation of a streptococcal species on culture, with microaerophilic streptococci identified in sixteen. Twenty (49 per cent) of the forty-one patients had isolation of a staphylococcal species. Four of the staphylococcal organisms were identified as oxacillin-resistant Staphylococcus aureus. Two patients who had three abscesses each had different organisms in each abscess. Gram-negative bacilli were identified in the cultures of ten (24 per cent) of the forty-one patients; patients who were forty years old or more had a sixfold greater risk of having gram-negative bacilli. Specimens of the abscess had been obtained from thirty-six patients for culture from twelve to seventy-two hours after the first dose of antibiotics had been given. The microbiological findings in these cultures were similar to those in the cultures of specimens obtained from patients before antibiotics had been given. Five (14 per cent) of thirty-five patients who had been tested for the human immunodeficiency virus had a positive result. This finding emphasizes the importance of surveillance for and precautions against the human immunodeficiency virus in people who abuse drugs parenterally.

Compartment syndrome associated with infection of the upper extremity.

Compartment syndrome is a potentially devastating entity associated with a great variety of injuries, but to the authors' knowledge there are no known reports of infection documented as a cause. A retrospective review of 263 patients with upper extremity infections admitted to the orthopaedic infection ward during 1992 was conducted to identify patients with compartment syndrome directly associated with infection. Four patients' clinical presentations fulfilled the criteria: two presented with infection and compartment syndrome, and two developed compartment syndrome 2-12 hours after admission. All four had beta-hemolytic streptococci on initial culture; three of four grew Group A streptococcus. Fasciotomies and serial debridements were necessary. One patient ultimately underwent amputation through the elbow.