The Slipping Rib Syndrome: An Overlooked Cause of Abdominal Pain
In 1921, Alexander Tietze first described a syndrome characterized by a painful affliction of the costochondral cartilages (area between the ribs and costal cartilages).1 He described a benign, painful, nonsuppurative swelling involving one or more of the costochondral or sternoclavicular junctions. The following year, Davies-Colley described two women in whom severe abdominal pain was caused by atraumatic, spontaneous overriding of the ninth and tenth ribs.2 This syndrome has been dubbed Tietze syndrome, costal margin syndrome, clicking rib, rib tip syndrome, and now commonly slipping rib syndrome.3-5 Even though this disorder was described more than 60 years ago, it is often overlooked in the differential diagnosis of abdominal or chest pain.6,7 This article will review the diagnosis and treatment of the syndrome and present case examples.
The pathophysiology of the syndrome was further clarified by Holmes in 1941, and later by McBeath and Keene in 1975.3,4 They examined the gross and microscopic anatomy of the costochondral, sternal, and subcostal regions in normal individuals and identified recurring subluxation (dislocation) of the costal margins of the eighth, ninth, and tenth ribs due to hypermobility of their anterior edges. Actually, the rib tips do not sublux unless the fragile, fibrous articulations are disrupted. Unlike ribs one to seven, which are attached to the sternum, the eighth, ninth, and tenth ribs are attached only to each other by loose fibrous tissue. Paradoxically, when the fibrous tissue between the ribs is incised, they come in contact with each other and become locked behind the adjoining rib.
Holmes’ anatomic studies revealed that the cartilage ends curl upward inside the ribs so that they come in close relationship to the intercostal nerves.8 The fibrous hammocks surrounding the synovial membranes of the interchondral cartilages of the eighth, ninth, and tenth ribs also involve the terminal branches of the intercostal nerves. These nerves are particularly vulnerable to even trivial trauma. On careful examination, Holmes did not find the synovial membranes to be pathologic; thus, he concluded that the cause of the pain was recurrent, repetitive irritation of the intercostal nerves, not a synovitis of the interchondral cartilages. These factors support the hypothesis that direct or indirect trauma is the cause of the syndrome. The trauma may, at times, be completely covert and not directly implicated.4,9
Upon physical examination, the pain is clinically recreated when the rib margins are displaced upwards and anteriorly; thus, the “hooking maneuver” can be used to corroborate the diagnosis (Figures 1 and 2). In all our cases, local anesthesia intercostal blockade relieves the pain. We have found that the relief could be prolonged by infiltration of the subcostal rib margins. In several cases, this has completely relieved the pain permanently.
Our Clinical Experience
The slipping rib syndrome should be considered whenever a patient is referred with a complaint of upper quadrant abdominal pain of obscure and uncertain etiology, especially if it involves the subcostal upper quadrants of the abdomen. Most often all diagnostic studies had ruled out underlying visceral pathology. In many cases, the patients had already undergone abdominal explorations with negative findings. The pain is often confused with cholecystitis, subphrenic abscess, pleurisy, or hepatic pathology. As in many cases, the pain may radiate to the right lower quadrant mimicking appendicitis or renal lithiasis. In some cases, it may create epigastric symptoms of such proportion that myocardial infarction is suspected.
The diagnosis often can be made by physical examination. Palpation of the tips of the eighth, ninth, and tenth ribs or of the posterior intercostal margins often reproduces the pain. A sensation of clicking or slipping is felt beneath the examining hand when the hooking maneuver is applied. The hooking maneuver often aggravates or recreates the typical pain sensation, but often cannot be done due to severe sensitivity of the subcostal margins. If the pain is absent, the maneuver may reproduce it. The condition is most often unilateral10 and performing the maneuver on the contralateral side will not evoke a pain response. The diagnosis is further confirmed by intercostal local anesthesia nerve blockade of the eighth, ninth, and tenth ribs as well as subcostal infiltration. After the block has taken effect, the hooking maneuver will not evoke pain.
If a conduction block is used for diagnostic purposes only, then another block may be performed using the combination of local anesthesia 0.5% bupivacaine and 40 mg triamcinolone. This has been found to relieve the problem unless further trauma recreates the pathology. If residual pain persists, or should reoccur, then follow-up with another local anesthesia steroid blockade may be performed.
Prolotherapy also has been used with great success and prolonged amelioration of the syndrome.11 A more profound blockade may be obtained by the use of the extract of the pitcher plant (Sarapin). The duration of the anesthesia may be prolonged in difficult cases by use of a neurolytic block with phenol 6%. Alcohol should not be used due to the potential for severe neuritis. Our cases all responded to local anesthesia and steroids. Surgery and further injections were unnecessary.
First Case Example
A 34-year-old woman was referred to our pain clinic complaining of right upper quadrant pain of 4 months duration. The pain prevented her from teaching school and performing her activities of daily living. She rated her pain as 10 out of 10 on visual analog scale (VAS).
There was no history of trauma. The subcostal abdominal pain was aggravated by distention of the abdominal wall and there was associated nausea without vomiting. There were no other gastrointestinal (GI) symptoms. The pain was not affected by eating or taking antacids, belladonna, cimetidine, or other GI medication.
All laboratory and radiological studies, including abdominal computed tomography scan, were negative. A short trial of non-steroidal anti-inflammatory indomethacin 50 mg 3 times daily and supplemental hydrocodone 10 mg every 4 hours, did not alter the symptom complex. Deep palpation produced pain in the right upper quadrant, with pain radiating posteriorly to the upper dorsal back. Palpation of the margins of the eighth, ninth, and tenth ribs and anterior displacing of the rib margins enhanced the pain. Characteristic snapping or clicking was not induced when performing the hooking maneuver.
Based on the history, clinical, and laboratory findings, the patient was diagnosed with slipping rib syndrome and treated with intercostal blockade of the eighth, ninth, and tenth ribs in conjunction with subcostal local anesthetic and steroid infiltration.