A recreationally active woman had experienced intermittent left lower chest and upper abdominal pain for 16 months.
She had been assessed across several specialties and undergone extensive investigations without a clear explanation.
The important clue was mechanical – a focal click and shifting sensation beneath the left costal margin that could be reproduced by abdominal contraction, trunk rotation and targeted palpation. This case illustrates when clinicians should consider slipping rib syndrome and how dynamic ultrasound assessment may identify a disorder that is not evident on static imaging.
What is slipping rib syndrome?
Slipping rib syndrome is a clinical pain syndrome associated with symptomatic hypermobility of one or more lower anterior costal cartilages, most commonly ribs 8–10. Movement of the affected cartilage against or beneath the adjacent cartilage may produce focal lower chest-wall or upper abdominal pain, sometimes accompanied by clicking, popping, catching or a sensation that something is moving beneath the costal margin.
Laxity or disruption of the interchondral attachments is one proposed mechanism. Abnormal contact between adjacent cartilages may irritate the surrounding soft tissues or an adjacent intercostal nerve, although the precise pain generator is not fully established.
Lower costal-cartilage anatomy, particularly the attachment of the tenth rib, is variable. Mobility may therefore be physiological and asymptomatic. The clinically important finding is movement at the symptomatic level that reproduces the patient’s familiar pain.¹˒²
Slipping rib syndrome should be distinguished from twelfth-rib syndrome, which involves the floating lower ribs and more commonly causes flank, loin or posterior lower chest pain. It also differs from costochondritis, which usually presents with parasternal costochondral tenderness without a hypermobile lower costal-cartilage phenomenon.
Relevant anatomy
Ribs 1 – 7 are conventionally described as true ribs because their costal cartilages attach directly to the sternum. Ribs 8 – 10 are false ribs and contribute to the costal arch through interchondral or fibrous attachments rather than attaching independently to the sternum. Ribs 11 and 12 are floating ribs and have no anterior attachment to the costal margin.
The ninth and tenth cartilages are more anatomically variable than traditional diagrams suggest. Some tenth ribs have a firm connection to the costal arch, whereas others are more mobile. This reinforces the need to distinguish normal variation from symptomatic movement.¹
Figure 1. Simplified comparison of a normal costal margin and symptomatic movement of the tenth costal cartilage. Final anatomical labels and image licensing should be confirmed before publication.
Case History
A recreationally active woman in her thirties presented with a 16-month history of intermittent pain beneath the left lower rib margin. Her symptoms first developed during a prolonged respiratory illness, when she experienced frequent bouts of forceful coughing.
She could not remember a specific injury or traumatic event. However, she later began to notice pain during loaded twisting movements of the trunk, together with an occasional sensation of movement beneath the lower ribs.
The pain was usually a localised ache, but could become sharp and catching with certain movements or activities, including:
- Sit-ups and abdominal exercises
- Rolling over in bed
- Bending and twisting at the same time
- Coughing or sneezing
- Contracting the abdominal muscles
- Rowing
- Lifting from a low or deeply bent position
During more severe episodes, the pain travelled around the lower chest wall towards the upper abdomen and, occasionally, into the back and side of the chest.
She also described an intermittent clicking or shifting sensation beneath the left lower ribs. The click itself was not always painful, but larger movements reproduced the familiar sharp pain.
As a result of her symptoms, she had stopped rowing and loaded abdominal training, reduced the amount of running she was doing and avoided lifting from low positions. Her sleep was sometimes disturbed when rolling onto the affected side.
Although she remained able to work and carry out most day-to-day activities, the persistence of the symptoms was becoming increasingly concerning, particularly as she worried that an underlying chest or abdominal problem may have been missed.
Absolutely. I’d retain the clinical detail but break up the denser sections and make the important positive and negative findings easier to identify.
Previous assessment and screening
Over the preceding 16 months, she had been assessed in primary care, gastroenterology and physiotherapy. Several possible diagnoses had been considered, including intercostal muscle injury, costochondritis, thoracic spinal or costovertebral pain, and non-specific abdominal wall pain.
Investigations had not identified a clear cause for her symptoms:
- Routine blood tests, including inflammatory markers, liver and renal function, were unremarkable.
- Chest radiography showed no focal pulmonary or bony abnormality.
- Abdominal ultrasound found no hepatobiliary, splenic or renal pathology to explain the pain.
- Thoracic spine MRI showed no structural abnormality that correlated with her symptoms.
Previous treatment had included thoracic mobility exercises, postural rehabilitation, manual therapy and relative rest. Although these approaches helped to reduce some of the associated thoracic stiffness, they had no significant effect on the focal costal-margin pain or clicking sensation.
Screening for other potential causes was also reassuring. There was no history of significant chest trauma, inflammatory arthritis, known osteoporosis, malignancy, or previous thoracic or abdominal surgery. She reported no exertional central chest pain, unexplained breathlessness, haemoptysis, fever, weight loss, persistent unremitting night pain, gastrointestinal bleeding, urinary symptoms or dermatomal rash.
Cardiorespiratory assessment was unremarkable, with symmetrical respiratory excursion. Abdominal examination demonstrated a soft, non-tender abdomen with no palpable mass. Focused neurological and abdominal wall assessment did not reproduce her primary symptoms, with no sensory disturbance, allodynia or dermatomal pattern identified.
Clinical examination
There was no visible chest-wall deformity, swelling or skin change. Thoracic flexion combined with right rotation reproduced pain at the left anterior costal margin.
Examination of the thoracic spine, costovertebral joints and posterior ribs did not reproduce her primary symptoms, and there was no evidence of spinal or radicular pain.
More focused examination of the anterior costal margin identified several key findings:
- Focal tenderness over the left tenth costal cartilage
- Increased mobility of the symptomatic cartilage compared with the contralateral side
- Reproduction of her familiar sharp pain with gentle superior and posterior pressure
- A palpable click accompanying symptom reproduction
- Reproduction of the same concordant symptoms during active abdominal contraction in supine, with no equivalent symptoms on the right
The traditional hooking manoeuvre also reproduced her pain. However, this was uncomfortable and provided no additional diagnostic information beyond gentler, targeted palpation. It was therefore not repeatedly performed.¹˒³
Figure 2. Targeted palpation and dynamic examination of the lower costal margin. The hooking manoeuvre may reproduce symptoms but can be uncomfortable; gentle palpation is often better tolerated.
Dynamic ultrasound
Dynamic ultrasound assessment was performed using a high-frequency linear transducer, with the patient initially supine and then semi-reclined. The asymptomatic costal margin was examined first to establish her normal anatomy and provide a baseline comparison of rib and cartilage movement.
The eighth, ninth and tenth costal cartilages were then identified on the symptomatic left side. Assessment was performed at rest and during several provocative manoeuvres:
- A controlled abdominal crunch
- Gentle pressure beneath the tenth costal cartilage using the rib-push manoeuvre
- Deep inspiration
- Her usual movement from lying towards sitting
During provocation, the anterior left tenth costal cartilage was seen to translate deep to the adjacent ninth cartilage. Similar movement occurred during active abdominal contraction and her usual sit-up movement. Importantly, this reproduced her focal pain, palpable click and characteristic mechanical sensation.
Some mobility of the tenth rib was also observed on the asymptomatic side. However, this was painless and did not produce the same degree of cartilage overlap.
Figure 3a Dynamic Ultrasound at Rest: Costal-Margin Morphology
Adapted from Riemann M. Dynamic Ultrasound in the Evaluation of Patients with Suspected Slipping Rib Syndrome –
Part 2. American Institute of Ultrasound in Medicine.
Figure 3b. Dynamic Ultrasound During the Crunch Manoeuvre
Adapted from Riemann M. Dynamic Ultrasound in the Evaluation of Patients with Suspected Slipping Rib Syndrome – Part 2. American Institute of Ultrasound in Medicine..
Figure 3c. Dynamic Ultrasound During the Rib-Push Manoeuvre
Adapted from Riemann M. Dynamic Ultrasound in the Evaluation of Patients with Suspected Slipping Rib Syndrome – Part 2. American Institute of Ultrasound in Medicine.
Dynamic ultrasound can support the diagnosis of slipping rib syndrome by demonstrating rib and cartilage movement during symptom-provoking tasks.
In a 2019 specialist retrospective study, the complete dynamic ultrasound protocol identified 32 of 36 patients classified as having slipping rib syndrome, with the rib-push manoeuvre being the most sensitive individual manoeuvre.⁴
A larger 2025 paediatric retrospective study also reported high overall detection rates, although the individual morphology, crunch and push components demonstrated more moderate sensitivity than specificity.⁵ Importantly, much of the available evidence comes from specialist paediatric populations. Results may therefore not translate directly to all adult presentations or to clinicians with less experience of dynamic costal-margin ultrasound.
Dynamic ultrasound should therefore be used alongside, rather than as a replacement for, a thorough clinical assessment.
Diagnosis
The findings were most consistent with left-sided slipping rib syndrome involving a symptomatic hypermobile tenth costal cartilage.
The diagnosis was supported by several consistent findings:
- Focal pain and clicking at the lower anterior costal margin
- Mechanical provocation with trunk movement and abdominal contraction
- Greater tenth-cartilage movement on the symptomatic side
- Reproduction of her familiar pain and click with targeted palpation
- Corresponding cartilage movement and symptom reproduction during dynamic ultrasound
No single clinical or imaging finding was considered diagnostic in isolation. Rather, the diagnosis was based on the overall pattern of symptoms, examination findings and dynamic imaging.
Focused differential diagnosis
A number of alternative causes of lower chest-wall and upper abdominal pain were considered.
Rib stress or costal-cartilage injury:
A cough-related rib stress injury, costal-cartilage injury or interchondral injury remained a possible initial precipitating event. Repeated forceful coughing may have contributed to the subsequent development of symptomatic mobility.
Costochondritis:
This was considered less likely because her pain was centred around the lower anterior costal margin rather than the more typical parasternal costochondral junctions. The focal clicking and demonstrable movement of the tenth cartilage were also atypical.
Intercostal muscle injury:
This was a reasonable initial diagnosis given the onset following prolonged coughing. However, it became less likely as the presentation evolved, particularly because her principal symptoms were associated with discrete movement of the tenth cartilage rather than isolated loading of the intercostal musculature.
Thoracic spinal or radicular pain:
This was less likely because the symptoms did not follow a dermatomal distribution, neurological examination was reassuring and assessment of the thoracic spine and posterior ribs did not reproduce her familiar pain. The normal thoracic MRI provided further reassurance, although imaging alone cannot exclude all radicular causes.
Abdominal wall or neuropathic pain:
Abdominal-wall pain, anterior cutaneous nerve entrapment and intercostal neuralgia were considered. However, there was no sensory disturbance, allodynia or clear neuropathic pattern. Her principal symptoms were most consistently reproduced by movement of the tenth costal cartilage.
Other lower-rib syndromes:
Twelfth-rib syndrome and iliocostal impingement were less likely because the symptomatic structure was the anterior tenth costal cartilage rather than a floating rib or the lower rib–iliac crest interface.
Finally, the strongly mechanical nature of the presentation, absence of red flags and reassuring previous investigations made significant visceral or cardiorespiratory pathology less likely.
Management and rehabilitation
The mechanical nature of the symptoms and reassuring assessment findings were explained to the patient. Importantly, she was reassured that increased lower-rib mobility is not necessarily dangerous and does not automatically require surgical correction.
Initial management focused on reducing symptom irritability while maintaining general activity, followed by a progressive return to the movements and exercise that mattered to her.
For the first four weeks, she temporarily stopped rowing, full-range sit-ups, heavy loaded rotation and lifting from deep flexion. She continued walking, comfortable running and lower-limb training provided these did not provoke sharp or catching pain.
She was advised to avoid repeatedly palpating or manipulating the symptomatic cartilage. During more irritable periods, a log-roll technique was recommended when getting out of bed to minimise combined trunk flexion and rotation.
Simple analgesia was discussed, including paracetamol or a short course of anti-inflammatory medication where clinically appropriate and in the absence of contraindications. Regular analgesia was not considered necessary.
Physiotherapy programme
There is currently no validated physiotherapy protocol specifically for slipping rib syndrome, so rehabilitation was individualised according to her symptoms, functional limitations and goals.
The initial phase focused on:
- Relaxed breathing with lateral costal expansion
- Comfortable thoracic movement
- Low-load abdominal-wall activation
- Short-lever trunk control
- Aggressive direct mobilisation of the symptomatic cartilage was avoided.
As symptoms became less irritable, loading was progressively increased to include resisted anti-rotation exercises, modified side-bridge variations, loaded carries and controlled trunk flexion and rotation.
Lifting was initially performed from waist height and gradually progressed towards floor level. Rowing-specific pulling exercises and more demanding trunk-loading drills were then reintroduced.
Progression was guided by symptom response. A level of discomfort was considered acceptable provided there was no substantial deterioration later that day and symptoms had returned towards baseline by the following morning.
Importantly, a painless click was not regarded as evidence of tissue damage or an automatic reason to stop exercise. The aim of rehabilitation was to restore movement tolerance, trunk capacity and confidence, rather than to suggest that exercise could permanently reposition the cartilage or repair an interchondral attachment.
Escalation plan
As the diagnosis was clinically convincing and her symptoms remained manageable, injection treatment was not considered necessary initially.
An ultrasound-guided local anaesthetic intercostal or pericostal block was reserved as an option for persistent function-limiting pain, diagnostic uncertainty or when temporary analgesia might assist clinical decision-making.
Any response to injection would need to be interpreted cautiously. Pain relief would support the presence of a local pain generator but would not, in isolation, confirm slipping rib syndrome because local anaesthetic can spread to adjacent structures.
Specialist thoracic surgical assessment would be considered if symptoms remained persistent and disabling despite an appropriate period of conservative management and rehabilitation.
Several surgical techniques have been described, including:
- Costal-cartilage excision
- Sutured stabilisation
- Vertical rib plating
- Costal-margin reconstruction
Published outcomes are generally favourable, but the evidence is largely derived from retrospective specialist-centre case series. Recurrence and reoperation have been reported, and no single surgical technique has been established as universally superior.¹˒⁶–⁸
Outcome
At 12-week review, the patient reported a clear reduction in both the frequency and intensity of her pain. Sleep was no longer routinely disturbed and she had returned to her usual running volume.
Everyday lifting and trunk movements were performed with greater confidence, although occasional discomfort remained with deeper flexion combined with rotation.
The clicking sensation had not completely resolved but was less frequent and was usually painless. She had gradually returned to rowing and loaded trunk exercise, using her symptom response over the following 24 hours to guide progression.
She had not required regular analgesia, local anaesthetic block or surgical referral.
The remaining mechanical symptoms were considered acceptable in the context of her substantial improvement in pain and function. She was advised to continue progressive rehabilitation, with further clinical review if symptoms again became persistently painful or functionally limiting.
Discussion
Slipping rib syndrome can be challenging to recognise because lower chest-wall and upper abdominal pain may initially suggest pulmonary, visceral or spinal pathology. Patients may therefore undergo multiple investigations before a mechanical costal-margin disorder is considered. Furthermore, the clinically relevant movement may not be demonstrated on conventional static imaging.
In this case, an important diagnostic clue was the focal click at the tenth costal cartilage, particularly because targeted palpation and abdominal contraction reproduced both the click and the patient’s familiar pain.
Comparison with the contralateral side was also important. Some tenth-rib mobility was present on the asymptomatic side, demonstrating that movement alone should not be considered diagnostic. The location and degree of movement, reproduction of concordant symptoms and consistency with the patient’s clinical history are more meaningful than the ultrasound appearance in isolation.
The traditional hooking manoeuvre has historically been associated with the diagnosis of slipping rib syndrome but can be uncomfortable for patients. Gentle targeted palpation along the costal margin, combined with patient-specific provocative movements, may provide the necessary clinical information without repeatedly provoking severe pain.¹˒³
Dynamic ultrasound can then be used to assess the relationship between adjacent costal cartilages during a crunch, rib-push manoeuvre or the patient’s own symptom-provoking movement. However, it should be regarded as an operator-dependent adjunct to clinical assessment rather than a mandatory or definitive diagnostic test.
Evidence supporting specific physiotherapy programmes for slipping rib syndrome remains limited. Conservative management should therefore be presented as an individualised approach aimed at reducing symptom irritability, maintaining activity and confidence, and progressively restoring tolerance to functional loading.
Importantly, persistent painless clicking does not necessarily represent treatment failure. In this case, the mechanical sensation remained to some extent, but pain and function improved substantially.
For patients whose symptoms remain disabling despite appropriate non-operative management, referral to a thoracic surgeon with experience in costal-margin disorders should be considered. Surgical options are available, but treatment decisions should reflect symptom severity and functional limitation rather than the presence of rib mobility or clicking alone.
Learning points
- Consider slipping rib syndrome when focal lower costal-margin or upper abdominal pain is accompanied by clicking, catching or a shifting sensation.
- Lower-rib mobility alone is not diagnostic. Movement should correspond to the symptomatic level and reproduce the patient’s familiar pain.
- Gentle targeted palpation and contralateral comparison may be better tolerated than repeated use of the hooking manoeuvre.
- Dynamic ultrasound can demonstrate movement during provocative tasks but is operator dependent and should complement clinical assessment.
- Rehabilitation should restore movement tolerance, trunk capacity and confidence rather than claim to reposition the cartilage.
- Consider specialist surgical assessment when symptoms remain disabling despite proportionate non-operative management.
References
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