The septum is the midline partition within the nose dividing it into left and right nasal cavities. The commonest problem resulting from a bent septum is a blocked nose. Occasionally, this may cause a twist in the external shape of the nose as well. A bent septum may predispose some people to have chronic sinus problems.A septoplasty is an operation designed to straighten a bend/deviation in the septum of the nose and thus improve nasal airflow.