Slipping rib syndrome

Slipping rib syndrome, also known as Cyriax syndrome, occurs when hypermobility of the rib cartilage of the lower ribs slips and moves, leading to pain in the lower chest or upper abdomen ¹.

Epidemiology

This condition may occur at any age, but is reportedly more common in middle-aged adults, and is a recognised cause of recurrent lower chest and/or upper abdomen pain in adolescents.

This disorder appears to be less common in young children because of the pliability of their rib cage. There is no significant gender difference.

Clinical presentation

• intermittent sharp stabbing pain in the upper abdomen or back, followed by a dull, aching sensation
• slipping, popping, or clicking sensations in the lower ribs
• worsening of symptoms with certain manoeuvres, such as when bending, lifting, twisting or turning in bed
• palpation of the affected rib will reveal a tender spot on the costal margin and reproduce the specific pain
• pain is also reproduced by performing the hooking manoeuvre, where the clinician places his fingers in the subcostal area and pulls in the anterior cranial direction ^7,8

Most cases of slipping rib syndrome occur unilaterally, but the condition has been reported to occur bilaterally.

Pathology

The exact cause of slipping rib syndrome is not well understood. Slipping rib syndrome might occur after a trauma, injury, or surgery, but cases have been reported without any notable injuries.

It is believed to be a result of hypermobility of the rib cartilage (costochondral) or ligaments, particularly ribs 8, 9, and 10.

This slippage movement irritates the nerves and may strain the intercostal muscles in the area, leading to inflammation and pain.

Radiographic features

Cyriax syndrome is usually a clinical diagnosis but the presentation of symptoms overlap with possible intrathoracic or intra-abdominal pathology. Imaging may be necessary to exclude these.

Ultrasound

Dynamic ultrasound may demonstrate slipping of the costochondral region of the rib ³.

Treatment and prognosis

• analgesia
• modifying activity
• corticosteroid or local anaesthetic intercostal nerve block injections help to relieve pain
• if the condition persists or causes severe pain, surgery (e.g. costal cartilage excision ^4,5, minimally invasive repair ¹²) may be required  although costal cartilage excision may not prevent late pain recurrence ¹¹

Complications

Pain can become severe enough to cause disability but the condition does not cause any other serious complications.

History and etymology

It was initially described in 1919 by Edgar Ferdinand Cyriax (1874-1955), specialist in mechanotherapeutics, Central Institute for Swedish Gymnastics, London ⁶.

Differential diagnosis

Other rib, lower chest and upper abdominal pathologies, such as: 

• cholecystitis
• oesophagitis
• gastric ulcers
• stress fractures
• muscle tears
• pleuritic chest pain
• costochondritis
• Tietze syndrome
• bone metastases

Practical points

• Cyriax syndrome is an often underdiagnosed condition
• knowledge of this syndrome can prevent a delay in diagnosis and prevent unnecessary laboratory and radiological investigations