Hi Bobby,
The symptoms of a sportsman's hernia are very much the same as an adductor strain in terms of location and aggravating factors. However, the main difference is that it will normally cause more pain and stiffness the day after play and resolve with rest.
The sportsman's hernia is essentially a tear in the adductor muscle close to its insertion on the pelvis. By tear, I don't mean a usual muscles tear, its normally a hole.
The way to test for it is to have your patient lying on their back with their knees bent, feet together and legs dropped to the side (i.e. the position you would stretch the adductors). Get the patient to push their knees together against your resistance (to test the adductors) and monitor the response. Then do the same again but this time ask the patient to contract their transverse abdominus - if there is less or no pain with this it normally indicates a sportsman's hernia.
In terms of treatment, it really depends on how acute/chronic the problem is. I would always try conservative management first. You can keep your patient active, even allow them to run as its the torsional stresses on the pelvis that aggravate the problem. You then need to work on their core strength to again stop those torsional stress on the pelvis. If the hernia is not too bad this should get rid of the problem. If it is not helping then surgery is the answer - but now they can do it arthroscopically so recovery time is reduced as no wound to heal