RESUMO
According to medical literature, fracture of the first rib is quite rare and the bilateral condition is especially rare. This type of fracture is usually associated with severe intrathoracic trauma and other bony or neurovascular injuries, thus can be considered as a harbinger of major trauma. However here we present three cases of low velocity first rib fractures without any major trauma or multisystem injuries. All the three patients were treated conservatively and did well on simple analgesics and rest and had no early or late complications. It can be seen that not all the first rib fractures are associated with major trauma or multisystem injuries. There is a variant of first rib fracture with low velocity injuries which is not associated with any major complications in contrast to majority of first rib fractures associated with high velocity injuries. Causative factor of such injuries may be violent muscular contraction of scalenus anterior or serratus anterior, but not direct trauma.