<unk>  is most frequent among adolescents with about 65% of cases presenting between 12–18 years of age. It is the most common cause of rapid onset<unk>  pain and swelling in people under 18 years old. It occurs in about 1 in 4,000 to 1 per 25,000 males per year before 25 years of age; but it can occur at any age, including infancy.
Testicular torsion
Epididymitis
Inguinal hernia
Hydrocele testis
Appendix of testis
Testicular rupture
Ovarian torsion
Penile fracture