What's the purpose of Phys di

The thyroid cartilage with the superior notch at C4 /C5. Cricoid cartilage C6. Thyroid gland C7. Know the location and know it is the lowest structure to move with swallowing. If the glands are felt they should be free of nodules and free to move when swallowing. It is no longer than 4cm at its largest normal dimension. Right can be slightly larger ................
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