Generality
The costal volet is a life-threatening medical condition characterized by the paradoxical movement of a group of at least three ribs that have sustained a fracture in at least two distinct places.
Typical symptoms of the costal volet are chest pain and dyspnea.
Being a dangerous condition, the costal volet requires appropriate and timely medical treatment.
Anatomical reference on the rib cage and ribs
The rib cage is the skeletal structure located in the upper part of the human body, exactly between the neck and the diaphragm, which serves to protect vital organs (such as the heart and lungs) and important blood vessels (aorta, hollow veins, etc.).
According to anatomy manuals, it includes:
- Posteriorly, the 12 thoracic vertebrae;
- Latero-anteriorly, 12 pairs of ribs (or ribs);
- Anteriorly, the costal cartilages and a bone called the sternum.
Each pair of ribs is connected to one of the 12 thoracic vertebrae; obviously, the left ribs emerge from the left side of the aforementioned vertebrae, while the right ribs emerge from the corresponding right side.
In their anterior end, the ribs articulate with the costal cartilages.
The space between the overlapping ribs is called the intercostal space.
In the intercostal space reside the so-called intercostal muscles - which play a fundamental role in "expanding the rib cage, during breathing - numerous nerve endings (intercostal nerves), arterial blood vessels and venous blood vessels.
What is the costal volet?
The costal volet is a potentially fatal medical condition, which consists of a partial or complete dissection of a group of ribs (at least three, fractured in at least two places) from the remaining rib cage.
This circumstance is extremely dangerous, because it can lead to respiratory failure. In fact, the group of low-cut ribs - which doctors call "segment" - can perform movements opposite to the physiological ones of the rest of the rib cage, compressing the lungs during the respiratory act.
In technical jargon, a movement with the aforementioned characteristics is called a paradox movement.
ANOTHER DEFINITION OF COSTAL VOLET
According to another definition, the costal volet is the paradoxical movement of a segment of the rib cage, caused by the fracture of 3 or more ribs in at least two points.
SYNONYMS OF COSTAL VOLET
The terms: mobile costal flap, mobile thoracic flap and are synonyms of costal volet flail chest.
Causes
At the origin of a costal volet c is generally a multiple fracture of the ribs. Multiple rib fractures are fairly common injuries, due in most cases to trauma to the chest. Hence, traumatic events represent the main causes of costal volet.
Please note: doctors speak of multiple rib fractures, when there are more than one fractured ribs and / or when the same rib fractures in at least two points.
POSSIBLE CAUSES OF A RIB FRACTURE
The traumatic events that most commonly cause the breaking of one or more ribs are: road accidents, falls on slippery ground or from stairs and game collisions during the practice of a "sporting activity."
Figure: Contact sports such as rugby are at high risk for rib fractures, so they are also a possible cause of rib volet.
Among the less common causes, a particular mention deserves: particularly strong coughs and repetitive movements during manual work or during certain sports (stress rib fractures).RISK FACTORS
Given the cause-and-effect relationship between them, the rib volet and multiple rib fractures share the same risk factors. Among the latter, the two most important are:
- Osteoporosis. It is a systemic disease of the skeleton, which causes a strong weakening of the bones. The weakening arises from the reduction of bone mass, which, in turn, is a consequence of the deterioration of the microarchitecture of the bone tissue.
Therefore, people with osteoporosis are more prone to fractures, because they have more fragile bones than normal.
Osteoporosis mainly affects the elderly population. - Neoplastic lesions of the ribs. A malignant tumor, originating in one rib, weakens the rib, making it more fragile and particularly susceptible to multiple fractures.
In the very young population, the costal volet is frequently associated with a congenital bone disease known as osteogenesis imperfecta.
Osteogenesis imperfecta is a rare pathological condition, supported by specific genetic mutations, which involves an increase in skeletal fragility, a reduction in bone mass and a marked susceptibility to bone fractures.
WHAT CAUSES THE PARADOX MOVEMENT?
To induce the paradoxical movement of the portion of the thoracic cage unglued (ie the so-called costal segment), are the changes in thoracic pressure with respect to the atmospheric pressure, occurring during normal breathing.
Indeed:
- During inspiration, the rib cage widens, thanks to the contribution of the diaphragm (which contracts and pushes the abdominal organs downwards) and the intercostal muscles. With the widening of the rib cage, the pressure inside the chest cavity becomes more lower than atmospheric and the air enters the trachea more easily.
In the presence of a costal volet, the reduction in pressure inside the thorax causes an "attraction towards the lungs of the segment of the unglued ribs. - During exhalation, the rib cage reduces its size (contracts), as the diaphragm and intercostal muscles relax. With the reduction in the size of the rib cage, the pressure inside the chest rises and this leads to expulsion of the air introduced previously.
In the presence of a costal volet, the increase in internal thoracic pressure pushes the segment of the unglued ribs outwards.
As the reader can notice, the movements of the costal segment, in the situations of inhalation and exhalation, are always opposite to those of the rest of the rib cage.
EPIDEMIOLOGY
The exact incidence of the costal volet is unknown.
However, according to reports from Anglo-Saxon hospitals, for every 13 patients who come to the hospital with a rib fracture, there is one suffering from costal volet.
Symptoms and Complications
Symptoms that a patient with costal volet usually experience are: severe chest pain and dyspnoea (or shortness of breath).
Chest pain has very specific peculiarities:
- Worsens during deep breathing;
- Worsens with the compression of the thoracic area, which has suffered the trauma;
- It gets worse after certain twisting or bending movements of the body.
Dyspnea is explained by the paradoxical movement of the segment of the ribs that is unglued: this represents an obstacle to normal breathing.
Please note: it is important to point out that chest pain is the typical symptom of a rib fracture, so it is natural that it is also present on the occasion of costal volet.
TYPICAL SIGNS
On the thoracic area affected by the trauma, people with costal volet often have swelling and hematoma.
Like chest pain, these two clinical signs are also typical of all rib fracture situations.
COMPLICATIONS
The mobile rib flap can be fatal when it leads to pneumothorax associated with severe respiratory failure. In fact, in such conditions, the lungs stiffen and breathing gradually becomes more and more difficult.
The likelihood of complications is higher the more severe the trauma to the chest and the involvement of the ribs are.
Complication common to all rib fractures
A complication common to all rib fractures, and therefore also to those that do not cause costal volet, is the onset of pneumonia or lung infections of various kinds.
To induce the appearance of such conditions, sometimes very dangerous, is the inability to take deep breaths, due to the severe pain. It is for the latter reason that a crucial point in the modern therapy of rib fractures is the accurate treatment of the symptoms. painful.
Diagnosis
Doctors may suspect the presence of a costal volet starting from the physical examination, which mainly consists of evaluating symptoms.
However, to obtain more details, they must resort to some instrumental radiological examinations, such as chest X-ray (chest X-ray) and CT (Computed Axial Tomography).
OBJECTIVE EXAMINATION
The physical examination represents an obligatory step in the diagnostic process, as the information it provides outlines the basic problem and what caused it.
During its execution, the doctor visits the patient, looking for any external clinical signs (hematomas, swelling, etc.); in addition, ask the patient about the symptoms:
- What do they consist of?
- When did they appear? Did any event in particular trigger them?
- What movements or gestures sharpen the symptoms?
After the questionnaire, the physical examination ends with the palpation of the painful area (it is very important to understand if there is a paradoxical movement of a segment of ribs), the auscultation of the lungs and heart (in search of any abnormal sounds ) and the analysis of the head, neck, spinal cord and belly.
INSTRUMENTAL EXAMINATIONS
Chest x-ray (chest x-ray) and CT scan allow doctors to identify the exact location of the fractured ribs that cause the costal volet.
However, two aspects need to be clarified:
- Some rib fractures, especially those that are not clear or located on the sides of the rib cage, are poorly visible on chest x-ray.
- Doctors only use CT scans if the physical examination and chest X-ray did not provide the information necessary for a definitive diagnosis, which is very rare.
Treatment
Patients with a rib volet require immediate treatment.
The latter, in general, provides for:
- The administration of analgesics, i.e. pain relievers. Doctors typically prescribe a combination of opioids and NSAIDs (non-steroidal anti-inflammatory drugs). As far as opiates are concerned, the most used are some derivatives of codeine, known as hydrocodone and oxycodone; as for NSAIDs, on the other hand, the most prescribed are aspirin and ibuprofen.
The administration of analgesics, especially opiates, takes place by continuous epidural infusion, as it gives the best results. The infusion site is at the thoracic level, or at the supra-lumbar level. - Intubation and positive pressure mechanical ventilation. These two treatments serve to supply the patient with oxygen and to support him in breathing. They are indispensable whenever a rib fracture determines costal volet.
Typically, doctors stop such treatments as soon as lung function shows clear signs of recovery. - Making a thoracic drainage (or thoracic tube). It consists in the insertion, at the level of the pleural cavity, of a tube, which serves to remove air, blood and other possible fluids from the intrathoracic space. Doctors do it to reduce the risk of pneumothorax, which is one of the possible complications of positive pressure mechanical ventilation.
- The positioning of the patient so that he can breathe deeply and without pain. Together with analgesic treatments, it helps prevent the onset of pneumonia and lung infections.
SURGICAL FIXATION OF THE FRACTURE
More than 50 years ago, doctors often resorted to surgical fracture fixation, which is a surgical procedure aimed at speeding up bone welding.
After that, for various reasons, they felt it was appropriate not to use it anymore, because the risk of complications was higher than the benefits.
Lately, however, some studies have denied the above, showing that, if practiced in the very early stages, surgical fixation of the fracture can truly have positive effects on the patient and reduce the duration of positive pressure mechanical ventilation.
Prognosis
The prognosis depends on the timeliness of the diagnosis and on the application of the right treatments. A costal volet identified in time is treatable with a good chance of success.
