Biomedical subjects

Michael J Patzakis

Publications and source records attributed to Michael J Patzakis.

17 recordsLinked to original sources

PubMed2006

Septic arthritis in patients with human immunodeficiency virus.

The literature contains few descriptions of the infective organisms and diagnostic issues associated with musculoskeletal infections in patients with HIV. We retrospectively reviewed 19 patients with HIV treated at our musculoskeletal infection ward for septic arthritis. The mean CD4 count was 154/mm (range, 7-482/mm), and 11 patients had a CD4 count < 200/mm and were diagnosed with AIDS. The most common pathogen (six patients) was oxacillin-resistant Staphylococcus aureus. Mycobacterial infections occurred in three patients but no fungal pathogens were identified. Septic arthritis was monoarticular in 14 patients and involved the knee in eight patients, the hip in three patients, and the wrist in three patients. Five patients presented with polyarticular septic arthritis. All mycobacterial infections and four of the five polyarticular infections occurred in patients with a CD4 count < 200/mm. Patients with CD4 count < 200/mm had a lower joint fluid WBC count compared to patients with a CD4 count > 200/mm (40,500 vs 69,000/mm). Oxacillin-resistant Staphylococcus aureus was the most common pathogen. A high index of suspicion for Mycobacterium. tuberculosis arthritis and polyarticular septic arthritis is necessary in patients with HIV and a CD4 count < 200/mm.

AIDS-Related Opportunistic Infections↗

PubMed2006

Recalcitrant septic knee arthritis due to adjacent osteomyelitis in adults.

We asked whether adjacent osteomyelitis with acute septic knee arthritis explained a lack of response to initial management, and whether patient comorbidities predisposed to the nonresponsiveness. From 147 adult patients (151 knees) with septic arthritis, we identified 29 patients (33 knees) who had persistence or recurrence of symptoms after surgical drainage. Adjacent osteomyelitis was present in 31 (94%) of the 33 knees (27 of 29 patients) with poor response to treatment. Patients with adjacent osteomyelitis had more comorbid conditions (23 of 27 patients, 85%) than patients without osteomyelitis (64 of 120, 53%). The most common comorbid conditions in patients with adjacent osteomyelitis were diabetes mellitus (10 patients, 37%) and intravenous drug use (eight patients, 30%). We identified Staphylococcus aureus in 19 of 31 knees (61%) with osteomyelitis, eight (26% of total cases) of which were methicillin-resistant. Persistence of clinical signs of infection after surgical management of septic knee arthritis in adults should raise the suspicion of adjacent osteomyelitis, especially in patients with comorbid conditions. Additional imaging studies may be necessary to evaluate the distal femur and proximal tibia.

Adult↗

PubMed2005

Risk factors for respiratory failure following femoral fractures: the role of multiple intramedullary nailing.

Controversy exists on the relationship between intramedullary nailing (IMN) and the timing of fixation in the development of respiratory failure (RF) following femoral fractures. The purpose of this study is to identify risk factors for RF and evaluate the role of multiple IMN in the above setting. We prospectively observed 126 consecutive patients with femoral fractures for the development of RF. Twenty-one patients (17%) developed RF. This occurred before fracture fixation in 11 patients and after IMN in 10 patients; five after multiple IMN and five after a single IMN procedure. Patients who underwent multiple IMN demonstrated a significant increase of RF after fracture fixation (5/8,) compared to patients with one IMN procedure (5/114, 4.4%, p<0.001). Stepwise regression analysis identified two independent RF risk factors: thoracic injury and multiple IMN (odds ratios: 40.6 and 25.6, respectively). Thoracic injury and multiple IMN procedures are independent risk factors for RF in patients with femoral fractures, and the combination of the above conditions is highly predictive of the development of RF.

Adult↗

PubMed2005

Management of open fractures.

Open fractures are high-energy injuries that require a principle-based approach, starting with detailed evaluation of patient status and injury severity. Early, systemic, wide-spectrum antibiotic therapy should cover gram-positive and gram-negative organisms, and a common regimen is a 3-day administration of a first-generation cephalosporin and an aminoglycoside, supplemented with ampicillin or penicillin to cover anaerobes in farm or vascular injuries. Local antibiotic delivery with the bead pouch technique increases the local concentration of antibiotics, minimizes systemic toxicity, and prevents secondary wound contamination. Thorough irrigation and surgical debridement is critical for prevention of infection. Primary wound closure remains controversial because of concerns for gas gangrene. Partial wound closure is an alternative, with delayed wound closure within 3 to 7 days. In the presence of extensive soft tissue damage, local or free muscle flaps should be transferred to achieve coverage. Stable fracture fixation should be achieved with a method suitable for the bone and soft tissue characteristics. Early bone grafting is indicated for bone defects, unstable fractures treated with external fixation, and delayed union. A management plan guided by the above principles will achieve the goals of prevention of infection, fracture healing, and restoration of function in most of these challenging injuries.

Adult↗

PubMed2005

Microbiology of osteomyelitis in patients infected with the human immunodeficiency virus.

Osteomyelitis rarely develops in patients infected with the human immunodeficiency virus despite their immunosuppressed state. In the limited literature available on this subset of patients, the role of opportunistic micro-organisms is controversial. Our purpose is to describe the microbiologic features of osteomyelitis. This is a retrospective review of 20 patients infected with the human immunodeficiency virus who were admitted to our musculoskeletal infection ward with the diagnosis of osteomyelitis. Eleven patients (55%) were intravenous drug users. Medical comorbidities were present in 14 of 20 patients (70%), including tuberculosis in five patients and hepatitis C in three patients. The mean CD4 count was 269/mm (range, 20-539/mm). Osteomyelitis was monomicrobial in 10 patients (50%) and polymicrobial in seven patients (35%) whereas in three patients no organism was cultured. The most common pathogen was Staphylococcus aureus, present in 10 patients (50%). No mycobacterial or fungal pathogens were identified. Infection recurred in 3 of 14 patients (21%) that were available for followup. Despite their immunocompromised status, patients infected with the human immunodeficiency virus did not develop osseous infections with opportunistic pathogens. Staphylococcus aureus was the most common pathogen found; however, a considerable proportion of infections were polymicrobial.

AIDS-Related Opportunistic Infections↗

PubMed2005

Treatment of persistent infection after anterior cruciate ligament surgery.

Infection after anterior cruciate ligament reconstruction that persists despite debridement is a challenging problem with limited information available in the literature. Our purpose was to determine whether an aggressive protocol would be effective in treating these persistent infections. This is a retrospective review of five consecutive patients with persistent septic arthritis of the knee after anterior cruciate ligament reconstruction. All patients previously had one to three irrigation and debridement procedures that failed to control the infection. Our treatment protocol consists of arthrotomy, complete synovectomy, removal of any implants, graft removal, and curettage of the femoral and tibial tunnels. Cultures are obtained from many sources (joint fluid, synovial lining, graft, and bone) and antibiotic therapy is given for 6 weeks. At a median followup time of 20 months (range, 6-27 months) infection was controlled in all patients. Three of five infections (60%) were polymicrobial. In these cases, different organisms were cultured from multiple tissue samples. Tunnel osteomyelitis was present in three of five patients (60%). Persistent septic arthritis of the knee after anterior cruciate ligament reconstruction can be controlled with a protocol based on radical debridement. Polymicrobial infections may be present and multiple cultures from different sources are required to identify all pathogens.

Adult↗

PubMed2005

Chronic posttraumatic osteomyelitis and infected nonunion of the tibia: current management concepts.

Chronic posttraumatic osteomyelitis and infected nonunion of the tibia are complex problems that result in considerable morbidity and can threaten viability of the limb. Development of infection may result from compromised soft tissue and bone vascularity, systemic compromise of the host, and virulent or resistant organisms. Biofilm formation on implant and devascularized bone surfaces protects pathogens and may lead to persistence of infection. Management is based on a detailed evaluation of the patient, the involved bone and soft tissues, degree of associated lower extremity injury, and type of bacterial pathogens. Infection control is achieved with radical débridement, skeletal stabilization, and microbial-specific antibiotics. Local antibiotic delivery is a useful supplement to systemic administration. Local or free muscle flaps may be necessary to achieve soft-tissue coverage. Restoration of bone defects and bony union can be accomplished with bone grafting. However, large defects require complex reconstructive procedures, such as distraction osteogenesis and vascularized bone grafting.

Chronic Disease↗

PubMed2004

Local antibiotic therapy in the treatment of open fractures and osteomyelitis.

Local antibiotic therapy is part of the treatment protocol of open fractures and osteomyelitis. However, there are limitations in the literature evaluating the efficacy of the technique and controversies remain. Polymethylmethacrylate cement commonly is used as a delivery vehicle, but bioabsorbable vehicles are being investigated. The vehicle is impregnated with antibiotic(s) active against the suspected pathogens, usually an aminoglycoside and/or vancomycin. Elution depends on the surface area, the characteristics and permeability of the delivery vehicle, type and concentration of the antibiotic(s) used, presence of fluid, rate of fluid turnover, and time postimplantation. Local antibiotic therapy is a safe technique resulting in high local concentration of antibiotics with minimal systemic levels. Local antibiotics effectively have controlled infection in animal models and, despite limitations of the existing literature, seem to be useful in the clinical setting. The length of implantation and the need for removal of the delivery vehicle remain controversial. Nonabsorbable vehicles may eliminate the need for reoperation and removal.

Animals↗

PubMed2004

Porcine small intestine submucosa does not show antimicrobial properties.

The goal of this study is to examine whether porcine small intestine submucosa (SIS) exhibits antimicrobial properties in a standard in vitro system, without pretreatment with acetic acid or extraction of soluble proteins. Previous animal studies suggest that porcine SIS may have inherent antibiotic properties. Using the guidelines for disk diffusion susceptibility testing by Bauer, 17/64-inch diameter disks made of porcine small intestine submucosa and of gortex were compared with standard antibiotic-impregnated disks against six organisms. The zone of inhibition was measured after 24 hours and minimum bacterial concentrations were determined by serial dilutions of a solution in which porcine small intestine submucosa was allowed to elute for 24 hours. Neither porcine SIS or gortex discs caused inhibition of the growth of any organism. The porcine small intestine submucosa discs showed bacterial growth on top of the discs whereas the gortex did not. Neither the dilutional concentrations of the porcine small intestine submucosa eluent nor the gortex eluent inhibited the growth of any organism. These findings suggest that the porcine small intestine submucosa does not have intrinsic antimicrobial properties. The growth of bacteria on top of the porcine small intestine submucosa suggests that porcine small intestine submucosa itself may provide a favorable environment for the growth of bacteria. More research is necessary to decide what role porcine small intestine submucosa plays in the treatment of infected surgical sites.

Animals↗

PubMed2004

Infected fractures of the distal tibial metaphysis and plafond: achievement of limb salvage with free muscle flaps, bone grafting, and ankle fusion.

Infection after fractures of the tibial plafond is a challenging problem that may even result in amputation. The current study evaluates a limb salvage protocol and the associated long term functional outcome in 6 patients (mean age 46 years) who were treated for infection after a fracture of the distal tibial metaphysis and plafond. Our limb salvage protocol included 3 stages: 1) radical debridement and stabilization of the ankle with a bridging external fixator, 2) soft tissue coverage with free muscle flaps, and 3) ankle fusion using iliac crest bone graft for filling the existing defects measuring 4.2 cm on average. At a mean followup of 5.5 years (range, 2-10.5 years), limb-salvage and eradication of infection was accomplished in all extremities. Fusion of the ankle joint was achieved in all patients, with one patient requiring a supplemental bone grafting procedure for delayed healing of the fusion site. All patients are able to walk without assistive devices and five of six patients are pain free. Limb salvage with free muscle flaps, bone grafting, and ankle fusion is a viable option for the treatment of infected tibial metaphysis and plafond fractures.

Adult↗

PubMed2003

Gunshot femoral shaft fractures: is the current classification system reliable?

The reliability of the AO/Orthopaedic Trauma Association classification system has not been evaluated for diaphyseal fractures or fractures attributable to gunshot injuries. Therefore, the current authors assessed its reliability for diaphyseal femur fractures and investigated the effect of a gunshot mechanism of injury. Forty-seven diaphyseal femur fractures, 23 caused by gunshots and 24 caused by blunt trauma, were classified by four observers on two occasions. The interobserver and intraobserver reliability of each level of the AO/Orthopaedic Trauma Association classification was assessed with kappa statistics. Determination of fracture type had substantial interobserver and intraobserver reliability for gunshot and blunt injuries. Reliability decreased at the subsequent levels of the classification. Fractures caused by gunshots compared with those caused by blunt trauma were characterized by significantly lower interobserver agreement on fracture group (k = 0.26 versus 0.45) and subgroup (k = 0.21 versus 0.38). The AO/Orthopaedic Trauma Association classification system has substantial interobserver and intraobserver reliability when evaluating the type of diaphyseal femur fractures. Determination of fracture group and subgroup, however, progressively reduces the reliability of the classification, especially for fractures caused by a gunshot. Diaphyseal femur fractures caused by gunshots, by means of their fracture patterns, cannot be classified reliably with the AO/Orthopaedic Trauma Association classification system.

Femoral Fractures↗

PubMed2003

Laboratory monitoring in pediatric acute osteomyelitis and septic arthritis.

The purpose of the current study was to determine the usefulness of erythrocyte sedimentation rate and C-reactive protein in pediatric bone and joint infections treated with and without surgery. The medical records of 50 patients admitted for acute osteomyelitis, septic arthritis, or both were reviewed retrospectively. There were 22 patients with septic arthritis, 20 with osteomyelitis, and eight with osteomyelitis with adjacent septic arthritis. There were 25 patients each in the surgical and nonsurgical groups. There was a statistically significant difference between the two groups regarding mean days to peak and normalization of erythrocyte sedimentation rate values and normalization of C-reactive protein values. Statistically significant differences were revealed for the mean days to normalization of erythrocyte sedimentation rate and C-reactive protein values among the patients with a diagnosis of osteomyelitis, septic arthritis, or both. The mean days to peak and normalization for erythrocyte sedimentation rate and C-reactive protein were twice as long in the surgical group as compared with the nonsurgical group. Complete recovery was achieved by all patients. This information should help the clinician in the diagnosis and treatment of children having surgery for acute osteomyelitis and septic arthritis.

Acute Disease↗

PubMed2003

Musculoskeletal sepsis: principles of treatment.

Musculoskeletal sepsis is infection of bone, joints, muscles, and skin and often occurs after open fractures. Thus, the main objective in the treatment of open fractures in restoration of function and prevention of infection. It is important to consider all open fracture wounds as contaminated. The principles of open fracture treatment include taking appropriate cultures, instituting immediate systemic antibiotic therapy, surgical débridement and wound management, stabilizing the fracture, and early bone grafting when indicated. The open tibial fracture, classified according to Gustilo and Anderson, serves as an exemplary model for musculoskeletal sepsis because this type of injury is described extensively in the literature. Early diagnosis and effective surgical and antibiotic management can control musculoskeletal sepsis, and the suppression of infection may last a lifetime.

Anti-Bacterial Agents↗

PubMed2003

Newer methods of antimicrobial delivery for bone and joint infections.

The advantages of systemic therapy include the ability to deliver antibiotics to areas that cannot be reached with topical therapy, the choice of a large selection of agents directed against the pathogens encountered in orthopaedic infections, and arrest or eradication of infection in most cases (in conjunction with adequate débridement). Disadvantages include the potential for toxicity from systemic agents, difficulty in achieving high concentrations of antimicrobial agents at the site of infection, and problems with compliance. To combat these disadvantages, newer methods for the delivery of antimicrobial agents have been investigated. Some of these newer methods include new formulations of antimicrobial agents to decrease systemic toxicity and improved methods for delivering local antimicrobial therapy.

Absorbable Implants↗

PubMed2002

Osteomyelitis attributable to vancomycin-resistant enterococci.

Vancomycin-resistant enterococcus first was described in 1988, and has become a major problem in nosocomial infections. This is a retrospective review of 10 patients, seen at the authors' hospital during a 2-year period, with confirmed vancomycin-resistant enterococcal osteomyelitis: four patients had total joint arthroplasty infections, one patient had an infected tibial nail, three patients had infections associated with external fixators, and two patients had osteomyelitis of the femur. Four of the 10 patients had underlying medical illnesses (diabetes mellitus, systemic lupus erythematosus, human immunodeficiency virus infection); four of the 10 patients were intravenous drug users. Two patients had vancomycin-resistant enterococci on admission, and the other eight patients were admitted to the hospital for a mean of 21.3 days (range, 3-73 days) before vancomycin-resistant enterococci were identified in the bone. Eight of the 10 patients had monomicrobial infections with vancomycin-resistant enterococci. Patients were treated by surgical debridement, removal of hardware, and antibiotics (chloramphenicol in eight patients, quinupristin and dalfopristin (Synercid) in two patients). All patients initially improved with therapy, but one patient had a recurrence of vancomycin-resistant enterococcal osteomyelitis and died of bacteremia. Bone infections with vancomycin-resistant enterococcus still may be uncommon, but with time and selective antibiotic pressures, vancomycin-resistant enterococci may become a more prominent entity in orthopaedic infections.

Adult↗

PubMedDate not supplied

The early diagnosis of sacroiliac joint infections in children.

UNLABELLED: We retrospectively reviewed the medical records and imaging studies of 15 children with infections of the sacroiliac joint to determine the usefulness of specific examinations and studies to aid in the early diagnosis of this condition. The clinical presentation, physical examination findings, pertinent laboratory data, and imaging studies were reviewed. Thirteen patients (87%) were febrile at the time of presentation. One patient presented in septic shock requiring intubation and critical care management. Tenderness to palpation over the sacroiliac joint was present in all 9 patients who had this examination performed, and the flexion abduction external rotation test was positive in 10 of 12 patients (83%) who had this test done. Laboratory indicators of infection were elevated in most patients, and 6 patients (46%) had positive blood cultures, most commonly growing Staphylococcus aureus. Initial conventional radiographs were negative in all but 1 patient. Radionuclide 99-m-technetium bone scans were positive in 7 of 10 patients (70%), and magnetic resonance imaging studies were ultimately positive in 13 of 14 patients (93%). However, within the first 6 days after the onset of symptoms, only 5 of 8 bone scans (63%) and 5 of 9 magnetic resonance imaging studies (57%) were consistent with infection. We conclude that while diagnostic imaging studies are ultimately helpful in confirming the diagnosis of sacroiliac joint infections in children, studies made within 6 days of the onset of symptoms may not always confirm the diagnosis. The early diagnosis of this condition is best made on the basis of clinical and laboratory findings. LEVEL OF EVIDENCE: Therapeutic Study, level IV (Case series [no, or historical control group]).

Adolescent↗

PubMedDate not supplied

Open fractures: evaluation and management.

Open fractures are complex injuries that involve both the bone and surrounding soft tissues. Management goals are prevention of infection, union of the fracture, and restoration of function. Achievement of these goals requires a careful approach based on detailed assessment of the patient and injury. The classification of open fractures is based on type of fracture, associated soft-tissue injury, and bacterial contamination present. Tetanus prophylaxis and intravenous antibiotics should be administered immediately. Local antibiotic administration is a useful adjunct. The open fracture wound should be thoroughly irrigated and debrided, although the optimal method of irrigation remains uncertain. Controversy also exists regarding the optimal timing and technique of wound closure. Extensive soft-tissue damage may necessitate the use of local or free muscle flaps. Techniques of fracture stabilization depend on the anatomic location of the fracture and characteristics of the injury.

Fractures, Open↗