Diagnostic Value of Dynamic High-frequency Ultrasound for the Slipping Rib and Twelfth Rib Syndrome: A Case Series with Review

Background: High-frequency ultrasound (HFUS) is a mobile, radiation-free imaging tool for the diagnosis of musculoskeletal disorders. We aim to demonstrate the diagnostic value of dynamic HFUS for undiagnosed lower chest, upper abdomen, and loin pain with this case series. Case Series: A cricketer presented with long-standing left-sided dull ache lower chest and upper abdominal pain, aggravated on exertion and leaning forward. His previous laboratory and previous imaging tests were unrevealing. Dynamic HFUS of his left ribs during hooking maneuver demonstrated slipping of the eighth rib over the seventh rib associated with clicking. He also reported tenderness over this region. He was diagnosed with slipping rib syndrome (SRS), and was treated with the eighth nerve block under the HFUS guidance. The second and third cases presented with chronic undiagnosed waxing and waning loin pain despite extensive laboratory and radiological workup. Both patients demonstrated twelfth rib HFUS probe tenderness in a sitting position with a specific movement that reproduced the pain during the dynamic HFUS study. The diagnosis of twelfth rib syndrome (TRS) was confirmed and treated successfully with a local intercostal nerve block. Review of the Literature: HFUS is the most underutilized imaging tool for the diagnosis of unexplained upper abdominal and lower chest pain syndromes. We identified only a few such reported cases managed with the help of HFUS. Conclusion: The dynamic HFUS is a valuable imaging modality for the undiagnosed lower chest, upper abdominal, or loin pain.