The nasal septum is the wall dividing the nose into halves and should ideally be exactly midline. However, 80 % of all nasal septums are off-center. This deviation occurs when the shift away from midline is severe. The most common symptom of a badly crooked septum is difficulty breathing through the nose. In some cases it may also interfere with the drainage of the sinuses resulting in repeated sinus infections. Other symptoms include frequent nose bleeds, post nasal drip, noisy breathing during sleep and nasal blockage.