Muscle Strain: Given the age and presentation, a muscle strain, particularly of the adductor muscles, is a common cause of groin pain in young males, often related to athletic activities or sudden movements.

Inguinal Hernia: Hernias are a frequent cause of groin pain and can be more common in younger males. The pain may worsen with coughing, lifting, or straining.
Epididymitis: Inflammation of the epididymis, often due to bacterial infection, can cause pain in the groin area that may radiate to the testicle.
Orchitis: Inflammation of one or both testicles, usually caused by bacterial or viral infections, can lead to groin pain.

Testicular Torsion: A medical emergency that requires immediate attention. It presents with sudden, severe testicular pain, often accompanied by nausea and vomiting. The pain can radiate to the groin.
Appendicitis: Although more commonly associated with right lower quadrant abdominal pain, appendicitis can occasionally present with groin pain, especially if the appendix is located in a retrocecal position.
Kidney Stone: A stone passing down the ureter can cause severe, colicky pain that may be felt in the groin area, often radiating from the flank.

Osteitis Pubis: Inflammation of the pubic bone and its surrounding structures, more common in athletes, can cause chronic groin pain.
Avulsion Fracture: A fracture where a fragment of bone is pulled away by a tendon or ligament, can occur in the groin area, especially in athletes.
Sacroiliitis: Inflammation of the sacroiliac joint, which can be due to various causes including inflammatory arthritis, can cause pain that may radiate to the groin area.