28: Paediatric Orthopaedics - The Limping Child Flashcards
what is a limp?
an abnormal gait commonly due to pain, weakness or deformity
what sort of questions would you ask about the history of presenting complaint in a child with a limp?
- duration and progression of limp?
- recent trauma and mechanism?
- associated pain and its characteristics?
- accompanying weakness?
- time of the day when limp is worse?
- can the child walk or bear weight?
- has the limp interfered with normal activites?
- any systemic symptoms e.g. fever, weight loss?
what should you look for when examining a child with a limp?
LOOK:
- check sole of foot for foreign bodies
- deformity? erythema? swelling? effusion?
- limitation of active ROM, asymmetry
- assess shoes for unusual wear on the soles, asymmetry , point of initial foot strike, assess fit of shoe.
- in older children, look for scoliosis, midline dimples and hairy patches which could indicate spinal pathology.
- assess gait with the child barefoot
- assess thigh or calf circumference for asymmetry
- leg length assessment
FEEL & MOVE:
- spine
- hip
- knee
- ankle
- foot
- Perform neurological assessment
what initial investigations should be performed in a child with a limp who is systemically unwell (fever, malaise etc.)?
- temperature
- bloods: WCC, CRP, ESR, CK, cultures
- x-ray?
- US?
septic arthritis clinical presentation
- limping
- pseudoparalysis
- swollen, red joint
- refusal to move joint
- pain
- temperature
what is the most common site for septic arthritis?
knee
septic arthritis investigations
Bloods:
- FBC & differential, raised WCC > 12,000/mm^3
- ESR > 50mm/hr
- CRP
- blood cultures +ve in 30-50%
Imaging:
- x-ray
- US - always be present!!
Synovial fluid analysis:
- WCC > 50,000/mm^3
- gram stain
- culture
what criteria is used to predict the chance of septic arthritis based on + tests?
Kocher criteria
describe components of the Kocher criteria
Criteria:
- pyrexia > 38 degrees celcius
- weight-bearing = no
- WBC count > 12,000/ml
- ESR > 40mm/hr
Chance of septic arthritis:
- 0 positive criteria < 0.2% chance
- 1 positive = 3% chance
- 2 positive = 40% chance
- 3 positive = 93.1% chance
- 4 positive = 99.6% chance
what are the most common causative organisms in septic arthritis?
- staph aureus (including MRSA) in 50% of cases
- streptococci (groups A, B, C or G) second most common
septic arthritis treatment
- perform blood cultures and joint aspiration before antibiotics, send for gram stain, culture, crystals and cell count.
- for gram + cocci (staph.areus and streptococcus) give IV flucloxacillin or clindamycin. If MRSA, give IV vancomycin.
- ## IV antibiotics for 2 weeks and orally for 4 more weeks.
what is osteomyelitis?
An acute or chronic infection of the bone, typically caused by bacterial organisms such as staph aureus and coagulase-negative staphylococci, although fungal causes are aslo possible.
acute osteomyelitis presentation
- fever
- pain at rest, worsening with weight-bearing
- swelling
- erythema of the affected site
what investigations should be performed in a patient presenting with symptoms suggestive of acute osteomyelitis?
- serum CRP, ESR, blood culture
- plain radiograph
If CRP or ESR elevated or abnormal radiograph:
- MRI
- bone scan
- CT
- bone biopsy
- or all of the above
what are the indications for surgery in osteomyelitis?
- aspiration for culture
- drainage of subperiosteal abscess
- drainage of joint sepsis
- debridement of dead tissue
- failure to improve
- biopsy in equivocal cases
