orthopaedic infections Flashcards
what are the risk factors for osteomyelitis?
diabetes
immunosuppression
surgical contamination
penetrating injury
what can cause the infection of the bone to develop?
haematogenous spread
peripheral vascular disease
prosthesis
what organisms can cause acute osteomyelitis?
staph aureus
streptococci
h.influenze
what organisms can cause chronic osteomyelitis?
TB
pseudomonas aeroigenosa
salmonella
ecoli
what is Potts disease?
TB infective spine disease that causes crush fracture of thoracic spine
what is salmonella osteomyelitis a complication of?
sick cell anaemia
what investigation is crucial for osteomyelitis ?
MRI
what is the treatment for acute osteomyelitis?
flucloxacillin (6 weeks) IV
clindamycin if allergic
vancomycin IV is MRSA
what is the treatment for chronic osteomyelitis?
antibiotics and debridement
flucloxicillin
MRSA or penicillin allergy:
co-trimoxazole or doxycycline
in prosthetic join infections, what causative organisms form early post operative?
staph aureus
in prosthetic join infections, what causative organisms form delayed post operative?
staph epidermis
propionbacterium acnes
in prosthetic join infections, what causative organisms form late?
staph aureus or E.coli
in early post operative infection, what is the time/route/presentation?
time: 0-3 months
route: perioperative
presentation: sepsis, warm joint with signs of effusion
in delayed post operative infection, what is the time/route/presentation?
time: 2-24 months
route: preoperative
presentation: persistent joint pain, loosening of prosthetic
in late operative infection, what is the time/route/presentation?
time: >24 months
route: haematogenous
presentation: acute or sub acute
what is prophylaxis for prosthetic joint infection?
co-amoxiclav (co-trimoxazole if allergic)
what is the therapy for prosthetic joint infection?
dependent on culture results/if implant retained or replaced given for approx 12 weeks gram postive: flucloxacillin/vancomycin gram negative: ciprofloxaxin if staph sensitive: rifampicin
what are the most common causes of septic arthritis?
1st: staph aureus
2nd: streptococci
what is the most common cause of septic arthritis in children?
h.influenza
what is the most common cause of septic arthritis in adolescents?
gonorrhoea
what it the most common cause of septic arthritis in the old/IVDU?
e.coli
what should you think if multiple septic arthritis?
endocarditis
what is the management of septic arthritis?
antibiotics +/- surgical wash out
fluxcloxacillin (clindamycin if penicillin allergic)
what antibiotic should be added if children to cover h.influenza?
ceftriaxone
what is and where does necrotising fasciitis happen?
severe subcutaneous tissue infection
most commonly abdominal wall, limbs and groin
what are the two types of causative organisms of NF?
type 1: mixed anaerobes and aerobes
type 2: group A strep
what is the management for NF?
start treatment before result obtained
debridement + antibiotics
IV penicillin + clindamycin
what causes gas gangrene?
cholstridium perfingens (sporm forming, gram positive bacillus that is a strict aerobe)
how does gas gangrene present?
usually following penetrative wound
skin discolouration
bubbling of the skin
what is the management of gas gangrene?
urgent debridement and antibiotics:
penecillin and metronidazole
what is the causative organisms of tetanus?
cholstridium tetani:
spore forming, gram positive bacillus that is a stoic anaerobe
drumstick shaped in culture
from rusty nails
how does tetanus present?
following penetrative trauma spastic paralysis lock jaw can affect breathing can be triggered by loud noises and bright lights
what is the management of tetanus?
surgical debridement
antibiotics - penicillin and metronidazole
anti-toxin
vaccine
