As the male organ develops in its early stages, sometimes the penile tissue develops off-center instead of presenting as a straight appendage. Penis curvature is a very common condition that can occur anywhere along the penile shaft and will deviate in any direction including up, down, and even sideways; a condition called a lateral curvature. Penis curvature that results from a congenital defect usually presents in a downward angle, also known as chordee, and is usually caused by scar tissue on the underside of the penis.
Lateral curvature is usually the result of a disparity in the lengths of the erectile tendons with the penis naturally curving toward the shorter side. Either the lateral or chordee presentations of penile curvature are usually congenital, meaning males are born with this particular condition.
During an erection affected by this condition, the resultant scar tissue limits expansion of the penis causing a curvature. Acquired penile curvature can also be the result of injury or sudden shock to the penis. Symptoms include thickening along the shaft, a bent profile, pain during an erection, and the inability to maintain an erection.