Sacroiliac (SI) joint pain and piriformis syndrome are widely recognized causes of low back pain. Accurate diagnosis of SI joint-mediated pain through physical examination and standard imaging modalities can be difficult. Fluoroscopic-guided SI joint injections can be both diagnostic and therapeutic and are currently the most reliable method for diagnosis. Treatment options include conservative modalities such as activity modification, physical therapy, medications, as well as interventional procedures, such as fluoroscopic-guided intra-articular injections, prolotherapy, and radiofrequency ablation. Surgical options may be beneficial for carefully selected patients with positive responses to an SI joint injection and who fail a nonsurgical, multimodal treatment approach.