ABSTRACT
The sternomastoid muscle divides the neck into two anatomical triangles. These are often referred to in clinical practice and in exams when describing lumps in the neck, and therefore an understanding of them is essential. The neck is divided into anatomical compartments by strong fascia, which is arranged in layers and tends to align neck structures in bundles. These are real and important anatomical divisions and have great relevance clinically. A history of pain or swelling in a neck lump usually indicates an inflammatory process; if these symptoms are clearly related to eating, and then sialadenitis/sialolithiasis must be suspected. Carcinomas that arise in the head and neck often metastasize to the regional lymph nodes in the neck. Fine-needle aspiration cytology is extremely useful in diagnosing the cause of many lumps in the neck. It is important to recognize that interpreting samples from this technique is difficult and demands an experienced cytologist.
