Spasmodic strictures and organic strictures are divided into two categories: 1. Spasmodic is a phenomenon of temporary difficulty in urination caused by strong contraction of the external urethral sphincter, often induced by urethritis, urethral stones, and the application of intraurethral instruments. 2, organic including congenital strictures and acquired strictures, congenital strictures such as those caused by hypospadias, narrowing of the external urethral opening and congenital narrowing of the urethral canal, prepuce, etc. Acquired strictures include the following four types: 1. Traumatic urethral strictures: including penetrating injuries (gunshot wounds), blunt injuries (straddling injuries, penile contusions) and crushing injuries (pelvic fractures). 2.Medicinal urethral stricture: commonly caused by intraurethral instrumentation or urethral compression necrosis or long-term indwelling urethral catheter. 3. Inflammatory urethral strictures: including chronic gonorrheal urethritis, tuberculosis infection and urethral strictures due to recurrent glans penis. 4.Sclerosing mossy urethral stricture. Urethral stricture caused by sclerosing mossy degeneration involving the urethra, manifested by whitening and hardening of the glans, narrowing of the urethral opening, and gradual development of urethral stricture to the proximal urethra.