Sacroiliac joint allows the pelvis to expand during childbirth, but both men and women have this joint. It’s an interlocking joint that should fuse after menopause. More common is females due to above, but can be seen in men. Pain usually an ache/throb and felt with buttock area (right over joint) and can radiation into thigh (not below the knee).
Treatment: physical therapy, Anti-Inflammatories, injections, or rhizotomy. There is no surgical fix for SI joint pain.