The painful rib syndrome

Sir,

The painful rib syndrome is thought to arise from the inadequacy or rupture of the interchondral fibrous attachments of the anterior ribs. This disruption allows for the subluxation of costal cartilage tips, impinging on the intercostal nerves. This may cause a variety of somatic and visceral complaints.[1,2,3,4,5] Although the diagnosis may be made based on history and physical examination, lack of recognition of this disorder frequently leads to extensive diagnostic evaluations before definitive therapy. We depict the case study of three patients with painful rib syndrome who presented within a year's time. The diagnosis had not been made prior to our consultation.

Case 1 – A 32-year-old woman complained of intermittent right loin pain over the previous 2 years. There were no associated symptoms and no history of trauma. The pain was preceded by certain activities such as sitting, leaning forward, and interestingly she found that using a swing machine was especially likely to produce discomfort. She had been extensively investigated and treated in various specialties with no result. On examination we found that manipulation of the tip of the right 12^th rib exactly and dramatically reproduced her pain. The pain was relieved completely following infiltration of 12^th rib tip with 2 ml of 1% lignocaine. The analgesia persisted for a time consistent with the expected duration of the local anesthetic. Successive intercostal nerve blocks with 5 ml of 0.25% bupivacaine and long-acting steroid methylprednisolone acetate (40 mg) under image intensifier produced complete pain relief. Patient again came with complaints of pain after 2 months of pain-free period. This time her pain was less in intensity. Intercostal nerve block was repeated with 5 ml of 0.25% bupivacaine and methylprednisolone (40 mg). On subsequent visits; she was pain free and was able to be more physically active without inducing pain.

Case 2 – A 40-year-old lady presented with acute right loin pain and a history of intermittent right loin pain for 10 months. The pains were initially sharp but then subsided into a dull ache lasting up to 2 days. The pain radiated to her right groin and subcostal region and was exacerbated by rotation of the trunk. Examination elicited extreme tenderness over the 12^th rib, and manipulation of that rib exactly reproduced her symptoms. A 12^th intercostal nerve block was performed using methylprednisolone (80 mg) in 5 ml of 0.25% bupivacaine. This pain was completely relieved and she did not complain of pain during her subsequent visit.

Case 3 – A 22-year-old female complained of sudden acute pain in left loin whenever she bent forward or attempted to lift anything heavy. She received analgesics, hot pack, and ultrasound treatment. During this period she experienced intermittent period of relief followed by relapses as she tried to increase her activity level. Tenderness over the 12^th rib was elicited during examination and confirmed to be the source of pain under image intensifier. Her pain was completely resolved, following successive 12^th intercostal nerve block with methylprednisolone (80 mg and 40 mg) in 5 ml of 0.25% bupivacaine.

The painful rib syndrome was first described in 1919[2] and officially named in 1922.[3] However, the first series of cases was not reported in the literature until nearly 20 years later. Cases have been reported in children as young as 12 years through individuals in their mid-80s, with the syndrome affecting females slightly more than males.[4,5,6] Bilateral cases have been reported but the condition is almost always unilateral, with pain localized to the tip of the 10^th, 11^th, or 12^th rib, which might be exacerbated by movement.[7]

The syndrome may be the result of trauma but many cases have been reported in which no thoracic or abdominal trauma had occurred. It is thought to arise from irritation of the intercostal nerve by the adjacent hyper-mobile rib cartilage. The anatomy of 12^th intercostal nerve can explain the variability in pain referral. The ventral ramus is larger than that of the other intercostal nerves, and gives a communicating branch to the first lumbar nerve.[8]

The diagnosis can be made simply in a clinical setting by direct examination and manipulation (hooking maneuver) followed with a rib block to see if the pain can be relieved. A majority of the cases may be treated by a frank discussion of the condition with the patient and a warning against those physical activities that tend to create such painful episodes. However, in patients with severe pain and dysfunction, nerve blocks and surgical intervention may be necessary.[6] In all of our patients, pain was completely resolved after intercostal nerve blocks. Local anesthetic and long-acting steroid infiltration to the tip of the affected rib will often produce complete pain relief at least for the duration of the local anesthetic and often long term. The procedure can easily be repeated if required. The immediate pain relief afforded by this procedure is often sufficient to reassure the patient of the “musculo-skeletal” pain diagnosis. In the event of short-term pain relief, more invasive procedure can be considered. These include intercostal nerve block, intercostal nerve cryotherapy, costo-vertebral blocks, percutaneous dorsal root ganglion radiofrequency thermocoagulation performed under image intensifier, and rarely rib excision.[8]

Painful rib syndrome is a fairly common condition and needs to be remembered as a possible cause of visceral and loin pain. Rapid diagnosis and treatment can markedly improve a patient's quality of life.