LOCO5 Flashcards
Define crush injury [1] and crush syndrome [1]
Crush injury:
* Injury caused as a result of direct physical crushing of the muscles due to something heavy.
Crush syndrome:
* Also termed rhabdomyolysis, involves a series of metabolic changes produced due to an injury of the skeletal muscles of such a severity as to cause a disruption of cellular integrity and release of its contents into the circulation.
Healing time
Define what clinical union is [1]
Define what radiological union [1]
Clinical union:
* the bones move as one and can be tender when stressed
Radiological union:
* Bridging callus formation
* Fracture line is often still present
* Remodelling
What is are early [4] and late [3] complication to soft tissue from trauma?
Early:
* Plaster sores
* Infection
* Neurovascular injury
* Compartment syndrome
Late:
* Tendon rupture
* Nerve compression
* Volkmann contracture
Define volkman contracture [1]
Volkmann contracture is a deformity of the hand, fingers, and wrist caused by injury to the muscles of the forearm.
The condition is also called Volkmann ischemic contracture.
What triad of things are you looking for with a fat embolism? [3]
Lung involement: causes hypoxaemia
Brain involvement: fat droplets get lodged in white matter in brain
Petachie: droplets get stuck in vessels and cause haemorrhage
What are the 6Ps of compartment syndrome? [6]
Which one is early? [1] and which is late? [1]
Pale
Pulseless
Parenthesis: first stage
Pain
Paralysis: late stage
Polar
How would a S. aureus infection appear in culture? [1]
Appears as grape like clusters, on trypticase soy agar plate produces yellow pigment: staphlyoxanthin
Why does acute blood born osteomyelitis affect children? [2]
Have a very rich blood supply to the bones, especially the metaphyseal ends of the long bones as this is where the growth plate is
The capillary loops near the metaphysis have slow flow/sluggish flow due to a rich blood supply here, meaning they are more at risk for bacterial invasion of the bone from the blood here
Describe how osteomyelitis causes abscesses to grow
- Bacteria enters the bone, it commonly lodges just below the epiphyseal growth plate
- Bone produces new bone around the bacterial infection to try and wall off and contain the bacteria in one location, however it walls it off yet this cannot be accessed by antibiotics as it is walled off.
- Can cause bone to die
Common consequences of osetomeylitis? [2]
Rare consequences of osetomeylitis? [2]
Common:
* Local bone loss
* Persistent drainage through sinuses
Rare
* Squamous cell carcinoma
* Amyloidosis
Risk factors for osteomyelitis? [6]
Age
Malnutrition
Impairment of local vascular blood supply:
* Diabetes mellitus
* Venous stasis
* Radiation fibrosis (radiation therapy damaging blood vessels)
* Sickle cell disease (due to crisis)
Describe how you diagnose osteomyelitis [4]
How does it appear on ultrasound? [2]
(same as SA)
Local non-specific pain
Elevated neutrophil count (< 50% of cases)
Elevated ESR
Ultrasound:
* Cortical thinning
* Inflamation
* Periosteal lifiting: abscess lifting it off
How do you treat chronic osteomyelitis? [5]
Puncture drainage if abscessed
Surgical debridement
Reconstruct bone (allograft/ autograft)
Antibiotics (4-6wks, at least 2 IV):
* Vancomyocin cement beads
* Flucoxallin (gram +ve)
* Clindamycin
* Piperacillin
* Ciprofloxacilin
How do you investigate for chronic osteomyelitis? [3]
MRI:
* Bone scintigraphy if MRI not available or suspicion of multifocal osteomyelitis - radiation that shows reactive bone
- Bone biopsy
- Blood samples
- Radiography
Why does joint infection occur when giving prosthetic bone / joint replacements occur? [2]
Where does it occur? [2]
Occurs in osseous tissue adjacent to prosthesis:
* bone cement interface
* bone contiguous with prosthesis (cementless devices)
Results from:
* local inoculation at surgery or post-op spread from wound sepsis
* haematogenous spread