What could cause a painful, swollen lymph node in neck?

Usually inflammation: Swollen lymph nodes in the neck are the sign of some form of pathology. Nodes don't enlarge spontaneously. When there is a malignancy of the oral cavity that spreads to lymph nodes they enlarge, become matted, and for the most part fix to jugular vein. Painful nodes are the sign of inflammation such as oral cavity or pharynx unassociated with tumor. Antibiotics may be necessary for control.