Bertolotti syndrome is a commonly missed cause of intractable back pain that affects 4% to 8% of the general population. It involves the congenital malformation of a transitional lumbosacral vertebra, with total or partial and unilateral or bilateral transverse process (TP) fusion or articulation to the sacrum. The pain can be debilitating, and the tethering of the spine to the sacrum can encourage deformity formation in the coronal plane and lead to early degenerative changes, especially if present only unilaterally. We present the case of a 24-yr-old woman with no notable prior medical history who presented with years of lower axial back pain radiating to her thighs, which limited her activities of daily living and was resistant to conservative management. Her imaging showed an abnormally large left L5 TP, which was articulated to the sacrum, and signs of early coronal deformity. She had responded almost completely to repeated steroid injections into the TP-sacral joint, but that effect was very transient. Informed patient consent was obtained prior to her surgery. She underwent a minimally invasive tube disconnection of the abnormal joint with partial distal resection of the TP, and her symptoms completely resolved. This case highlights the importance of correlating clinical symptoms with aberrant anatomy, and the role of selective surgery in providing symptomatic relief. This case report was written in compliance with our institutional ethical review board approval, and patient consent was waived in light of the retrospective and deidentified nature of the data presented in accordance with the University of Texas Southwestern institutional review board.