Trail's Sign

Shift of trachea produces prominence of sternal head of sternocleidomastoid on the side to which the trachea is shifted. It is called Trail's sign.

The pretracheal fascia encloses the clavicular head of stemomastoids muscle on both sides. When the trachea is shifted to one side, the pretracheal fascia covering the stemomastoid muscle on that side relaxes, producing the clavicular head more prominent on the side of tracheal deviation.

Causes of tracheal shift
Pleural disease - Shift to opposite side

• Pleural effusion
• Pneumothorax

Pulmonary disease-Shift to same side

• Fibrosis and collapse of lung

Note: Goiter - Shift of trachea to opposite side.