PM1071: Almost Slipped Through the Crack: A Case Report with Bilateral Slipped Rib Syndrome and Twelfth Rib Syndrome of the Eleventh Ribs

Introduction: Slipped rib syndrome is a rare and painful disorder in which there is hypermobility of the anterior false ribs, ribs eight to ten, resulting in the tips of the ribs moving or slipping under the superior rib. Slipped rib syndrome occurs when the false ribs lose their cartilaginous or fibrous attachment to one another, making them prone to misaligning and pinning under the adjacent ribs, impinging the intercostal nerve that is passing underneath the superior rib. Patients can present with a clicking or slipping sensation between their ribs, sharp and dull pain at the site that is possibly relieved with stretching, or generalized upper abdominal pain.

Alternatively, twelfth rib syndrome is caused by irritation of the twelfth intercostal nerve related to the hypermobility of the twelfth rib. Similarly, hypermobility of the eleventh rib can cause the same phenomenon. Pain from twelfth rib syndrome can be located more in the patient’s back.

Case Description: In this report, we present a case of a 17-year-old male with a history of Ehlers Danlos Syndrome who initially presented with debilitating pain lasting for about four months in the left posterior flank that persisted despite multiple medications and physical therapy. He was diagnosed with left-sided slipped rib syndrome and twelfth rib syndrome of the 11th rib which was treated with excision of the left eleventh rib and cryoablation of the left eleventh and twelfth intercostal nerves. The patient had complete resolution of the left-sided pain post-operatively. Less than one year later he developed right-sided pain that was very similar in nature to his previous left-sided pain and became debilitating. He was ultimately diagnosed with right-sided slipped rib syndrome and twelfth rib syndrome for which he underwent excision of the right ninth and tenth costal cartilage, cryoablation of the right ninth through twelfth intercostal nerves, and excision of the left eleventh rib. The patient then had complete resolution of his right-sided flank and anterior rib pain.

Discussion: A delineation between slipped rib syndrome and twelfth rib syndrome is important since they are both relatively rare, often misdiagnosed, and have different treatment algorithms.

Conclusion: Our case report is significant since our patient had both of these rare diseases, each of them required surgical intervention, and our patient had complete resolution of his symptoms post-operatively.