Symptoms of a groin strain include a popping sensation in the groin area at the moment of injury, tenderness in the groin and pain in the inner thighs, explains WebMD. Individuals with groin strains may also experience pain when lifting the knee or pushing the legs against one another.
Groin strains often occur during athletic activities and are classified in three grades, explains Kids Health. A grade 1 groin strain causes minimal symptoms and typically heals within a short period of time. A grade 2 strain may cause tightness and swelling in the affected area, and a grade 3 strain is diagnosed when the groin muscle suffers a complete or near complete tear.