Sciatica is a common syndrome mostly affecting adults. It has a wide range of etiologies, classified into intra- and extra-spinal, with intra-spinal being the most common, usually due to lumbar disc herniation causing nerve root compression. Sacroiliac (SI) joint pathologies are a known cause of extra-spinal sciatica syndrome, following multiple possible mechanisms. We report a case of a 33-year-old female patient who presented for non-resolving sciatica symptoms, found to have an inferior SI joint osteophyte compressing the sciatic nerve, who underwent surgical excision due to failure of conservative measures. All causes of sciatica related pain should be subjected to further investigations if not attributed clinically and radiologically to intra-spinal etiologies. SI joint imaging play an important role in the diagnosis of SI joint related sciatica, with the gold standard being an intra-articular anesthetic injection, to monitor for symptom relief in order to confirm the diagnosis, and choose the optimal treatment modality.