Osteomyelitis Flashcards
In children, microorganisms seed mainly in __________
long bones
In adults, the ____________ is the most commonly affected site
vertebral column
The most important aim of the management of osteomyelitis is to prevent progression to (acute/chronic) ___________ osteomyelitis
chronic
It is widely used classification system of osteomyelitis based on anatomic site, comorbidity, and radiographic findings
Cierny-Mader staging system
Three mechanisms underlying osteomyelitis
Hematogenous spread; spread of contiguous site following surgery; secondary infection of vascular insufficiency
In hematogenous osteomyelitis, the most common primary foci of infection are the ________, ________, _________, and the _________.
Urinary tract, skin/soft tissue, intravascular catheterization sites, endocardium
The most common underlying condition of osteomyelitis secondary to vascular insufficiency or peripheral neuropathy is __________.
diabetes
In poorly controlled diabetes, the _________ is caused by skin, soft tissue, and bone ischemia combined with motor, sensory, and autonomic neuropathy.
diabetic foot syndrome
In _____ (acute/subacute/chronic) osteomyelitis, it is treated with antibiotics alone.
acute
In _____ (acute/subacute/chronic) osteomyelitis, antibiotic treatment is combined with debridement surgery.
chronic
Subacute course of ________ osteomyelitis due to tuberculosis is caused mainly what specific type of low-virulence microorganisms?
vertebral; coagulase-negative staphylococci, P. acnes
Chronic osteomyelitis develops most often after ________, mandibular, or _____ infection
sternal, foot
Most common manifestation of hematogenous bone infection in adults
Vertebral osteomyelitis
Routes involved in pathogenesis of vertebral osteomyelitis
segmental arterial circulation; retrograde seeding through prevertebral venous plexus; direct inoculation during spinal surgery
Most common causative agent of acute vertebral osteomyelitis
S. aureus (40-50%)
Most common causative agent of subacute vertebral osteomyelitis
Mycobacterium tuberculosis
Most common causative agent of implant-associated osteomyelitis
coagulase-negative staphylococci and P. acnes
Leading initial symptom of vertebral osteomyelitis
Back pain
Most affected part in vertebral osteomyelitis
Lumbar spine (60%)
In implant-associated spinal osteomyelitis, early-onset infection is diagnosed within _____ days.
30
Diagnosis of vertebral osteomyelitis with high levels of sensitivity
ESR and CRP
When blood and tissue cultures are negative, what type of analysis should be used?
PCR
Reasonable first step in evaluating vertebral osteomyelitis
Plain radiography (Xray)
Useful in subacute or chronic cases, but NOT in acute osteomyelitis
Plain radiography (Xray)
Gold standard in diagnosing osteomyelitis
MRI
In antibiotic therapy in adults without implants, drug which can be used for DELAYED-type penicillin hypersensitivity
Cerufoxime (1.5g IV q6-8h)
In antibiotic therapy in adults without implants, drug which can be used for IMMEDIATE-type penicillin hypersensitivity
Vancomycin (1g IV q12h)
Epidural abscesses occur as complication of vertebral osteomyelitis in what part of spine?
Cervical (30%)
In antibiotic therapy in adults with orthopedic devices, drug which can be used for DELAYED-type penicillin hypersensitivity
Cefazolin (2g IV q8h)
In antibiotic therapy in adults with orthopedic devices, drug which can be used for IMMEDIATE-type penicillin hypersensitivity
Vancomycin (1g IV q12h)
This drug can be administered to patients with hypersensitivity to B-lactams
Ciprofloxacin (PO or IV)
Treatment for early staphylococcal implant-associated infections are _________ + ____________
Fluoroquinolone + rifampin
This drug is efficacious against staphylococcal biofilms < 3 weeks’ duration
Rifampin
Group of drugs which are effective against biofilm formed by gram-negative bacilli
Fluoroquinolones (ciprofloxacin, levofloxacin, ofloxacin)
Main complication of long-bone osteomyelitis
Persistence of infection with progression to chronic osteomyelitis
Favors the adherence of staphylococci and the formation of a biofilm that resists phagocytosis
Fibronectin / Collagen
Most common causative agent of prosthetic joint infection
S. aureus
Chronic PJI is commonly caused by what microorganisms
coagulase-negative staphylococci or P. acnes
Biomarker that can be tested in synovial fluid
a-defensin
Treatment of patients with severe comorbidity
Lifelong suppressive antimicrobial therapy
Most common causative agent of poststernotomy osteomyelitis
coagulase-negative staphylococci
Hematogenous sternal osteomyelitis common causative agent
S. aureus
Sickle cell anemia common causative agent
Salmonella
Common causative agent in IV drug users
P. aeruginosa
Feared complication of sternal osteomyelitis
Contiguous mediastinitis
Leading pathogen of foot osteomyelitis
S. aureus
Diagnostics for foot osteomyelitis which has 90% positive predictive value
probe to bone test
Anaerobes are prevalent in _____ (acute/chronic) wounds.
Chronic
Diagnostic test for foot osteomyelitis with high degree of sensitivity and specificity
MRI
Drug of choice against methicillin-resistant S. aureus
Vancomycin
TRUE or FALSE. Osteomyelitis is the inflammation of bone and marrow, always secondary to infection
TRUE
TRUE or FALSE. Pyogenic is almost always caused by bacterial infection
TRUE
What disease has a radiographic finding of a lytic focus of bone destruction surrounded by sclerosi
Osteomyelitis
Which is more destructive? Pyogenic or mycobacterial osteomyelitis?
Mycobacterial
Histological findings for TB caused by Mycobacteria
Granulomatous inflammation and caseous necrosis
Characteristic produced by reactive periosteal bone deposition on the medial and anterior surfaces of the tibia
saber shin
The ankle is a hinge joint formed by ______, the _____ and the _______
tibia, fibula, and talus
Principal joints of the ankle
Tibiotalar and subtalar (talocalcaneal) joints
Principal landmarks of the ankle
Medial malleolus - Tibia
Lateral malleolus - Fibula
Dorsiflexion and Plantar flexion are movements of what ankle joint?
Tibiotalar joint
This movement is powered by gastrocnemius, the posterior tibial muscle, and toe flexors
Plantar flexion
This movement is powered by the anterior tibial muscle, and toe extensors
Dorsiflexion
Ligament found medially involved in protecting against stress from eversion
Deltoid ligament
Ligament found laterally which s most at risk in injury from inversion
Anterior talofibular ligament
This tendon attached the gastrocnemius and soleus to posterior calcaneus
Achilles tendon
Muscles for eversion
Peroneus longus and brevis
Muscles for inversion
tibialis posterior and anterior
It also means “bend your heel outward”
eversion
It also means “point your foot toward the floor”
Plantar flexion
It also means “point your foot toward the ceiling”
Dorsiflexion