Septic arthritis of the hip
-Most common hematongenous spread
- Up to 20% of patients with non-gonococcal septic arthritis will have 2 or more joints involved –> always do a full musculoskeletal exam!
- 50% will have positive blood cultures –> always obtain cultures.
- Risk factors: Extremes of age, hardware/recent instrumentation, skin infection, underlying arthritis, IV drug use
- You cannot rule out septic arthritis with inflammatory markers or any physical exam findings, so err on the side of obtaining joint fluid.
Pediatric septic arthritis vs. transient synovitis
- Kocher criteria can help differentiate: Temperature >38.5, WBC >12K, ESR >40, unable to bear weight.
Contrast Extravasation
Spontaneous Pneumomediastnum
-Most common hematongenous spread
- Up to 20% of patients with non-gonococcal septic arthritis will have 2 or more joints involved –> always do a full musculoskeletal exam!
- 50% will have positive blood cultures –> always obtain cultures.
- Risk factors: Extremes of age, hardware/recent instrumentation, skin infection, underlying arthritis, IV drug use
- You cannot rule out septic arthritis with inflammatory markers or any physical exam findings, so err on the side of obtaining joint fluid.
Pediatric septic arthritis vs. transient synovitis
- Kocher criteria can help differentiate: Temperature >38.5, WBC >12K, ESR >40, unable to bear weight.
- 0/4: <0.2%, 1/4: 3%, 2/4: 40%, ¾: 93%, 4/4: 99.6
- Note: this was a retrospective study and external validation studies did not perform as well.
- Can not be used if patient recently on antibiotics.
Contrast Extravasation
- Monitor area for signs of compartment syndrome or airway compromise (depending on location)
- Complications rare now that we routinely use low-osmolar nonionic contrast
Spontaneous Pneumomediastnum
- Under recognized cause of chest pain
- Similar risk factors as spontaneous pneumothorax (asthma, tall, thin, valsalva, intense sporting activities)
- Alveolar ruptures into surrounding bronchovascular sheath and free air tracks into mediastinum
- Rarely causes tension physiology
- If history concerning for esophageal pathology, consider CT esophagram
- Treat conservatively by avoiding valsalva and barotrauma