It is usually considered a congenital malformation of unknown cause. Since at an early stage of fetal development the penis is curved downward, it has been proposed that<unk>  results from an arrest of penile development at that stage. The curvature of a<unk>  can involve # tethering of the skin with urethra and corpora of normal size; # curvature induced by fibrosis and contracture of the fascial tissue (Buck's fascia or dartos) surrounding the urethra; # disproportionately large corpora in relation to the urethral length without other demonstrable abnormality of either; or # a short, fibrotic urethra that tethers the penis downward (the least common type). Severe degrees of<unk>  are usually associated with hypospadias, but mild degrees of curvature may occur in many otherwise normal males. When the curved penis is small and accompanied by hypospadias, deficiency of prenatal androgen effect can be inferred.
Chordee
Wellbee
Charley horse
Botfly
White cane
Greenpilot
Zebra 
Cowlick