Not every spine sign is from pleural effusion
We have previously discussed the utility of ‘spine sign’ in diagnosing pleural effusion on POCUS. One of the short videos also talks about this. However, it is important to note that this sign is not specific to effusion. Anything that provides a medium for the ultrasound beam to pass through in the lower chest allowing visualization of vertebral bodies above the diaphragm gives spine sign. For example, lobar consolidation, pulmonary contusion or a mass can do this. Below is an illustrative image shared by Dr. Robert Jones. There is trace pleural effusion, but the spine sign is mainly coming from consolidation in this case.