Sacroiliac joint dysfunction
Sacroiliac joint dysfunction may present as pain along the superior aspect of the buttock adjacent to the L5 vertebrae. Pain is reproduced with lumbar flexion and extension. Atrophy of the lumbar extensors muscles or disuse often predisposes those to sacroiliac joint instability. Provocative testing on physical exam to confirm sacroiliac joint dysfunction includes pelvic distraction, compression, Gaenslen’s, FABERs (Flexion ABduction External Rotation), and thigh thrust. Treatment includes relative rest, NSAIDs, physical therapy, and joint injections.