Wat else can cause pain in the groin apart from hernia?

Injury, etc. Most younger men with groin pain have an injury, usually to the same structures that hurt when a hernia forms. Sporting activity can cause such pains (eg groin pulls etc) and the term "sports hernia" which some believe is more sports injury than hernia, can be made better by hernia-type procedures. The groin also contains lymph nodes, nerves, veins etc. An ultrasound and physical exam can help.
Pulling and scarring. On the nerves and muscles involved during the surgery will cause the pain. Take care!