Rib Fractures

The rib cage is a protective skeleton for the underlying structures in the thorax - namely the lungs, heart, great vessels and upper abdominal organs (liver and spleen).

For this reason the ribs are quite common bones to fracture (break).

Ribs can be fractured following falls, road traffic crashes and sports (contact sports such as rugby, boxing and more extreme sports such as snowboarding).

As we breathe, the lungs and ribcage expand as we inhale air and then return to their resting position when we breathe out (exhale).

On average humans breathe 16 times per minute, 960 times per hour and an amazing 23,040 times over 24 hours.

Thus fractured ribs are moved 23,040 times per day - hence the pain commonly associated with them.

Fractures in the limbs are normally immobilised in slings, splints or plaster casts - this is not possible with rib fractures.

Signs and symptoms

Rib fractures will normally be associated with some type of direct trauma to the ribcage.

The common symptom of a rib fractures will be pain - which is worse on breathing and may be reproducible when the area is pressed.

In cases of severe, multiple rib fractures patients may have difficulty spontaneously breathing

Diagnosis

The diagnosis of rib fractures is difficult. The diagnosis may be suspected from the signs and symptoms.

Chest radiographs (X rays) is often first line investigation but may only identify rib fractures in 10-30% of those with rib fractures - i.e. a 'normal' chest x ray does not exclude rib fractures.

The ribs are unique bones in that they behave somewhat like children's bones in adults - that is they do have some elastic properties and can buckle rather than break completely.

In a lot of cases even where the ribs have broken completely they remain in their natural position (splinted by the surrounding intercostal muscles that lie between the ribs).

CT (computerised tomography) scans facilitate view of the ribs in multiple planes (as a CT is effectively a 3D X-rsy) - making rib fractures easier to identify. However CT scans do require a much higher radiation exposure than a chest X ray. The CT scan must also be interpreted in multiple planes (traditionally axial, coronal and sagittal planes) to increase the ability to identify rib fractures.

Ultrasound is an increasingly used imaging modality for rib fractures. The main advantage is that it involves no radiation exposure. The use and interpretation of ultrasound is very much operator dependant, i.e. who is doing the ultrasound.

At OTL we have radiologists who are regularly imaging rib fractures and rib pathology using the three modalities above (with a particular interest in the use of ultrasound).

Treatment

The management of the majority of rib fractures is non-operative.

Pain management is one of the key issues. As mentioned previously the ribs and hence the fractures are constantly moving with our breathing cycle. This is often the most debilitating consequence of rib fractures.

Like other bones the ribs will heal naturally but this can take up to six weeks. Thus it is normal for rib fractures to remain painful for this duration and even beyond for up to twelve weeks. This is due to the fact that despite the bone healing in six weeks, the surrounding muscles and scar tissue may give soft tissue related pain for a further six weeks. In some cases the rib fractures may take longer to heal (delayed union) or not heal (non union)

The initial choices for pain control are:

Paracetamol. With regular use paracetamol is a very effective pain killer. It can be used in combination with other modalities of pain killer.

Non steroidal anti-inflammatory drugs. These drugs should be used sparingly around regular doses of paracetamol and as the pain improves their use reduced. one of the concerns with NSAIDs is the risk of them inhibiting fractures healing.

If these together do not control the pain other options include:

Opioids. There are a variety of opioid drugs which vary in their strength. The stronger opioids are controlled drugs only available by prescription from a doctor. They are very effective pain killers, but individuals will have varying sensitivity to opioids depending on their type of opioid receptor.

These drugs must be used with caution and for a short period as they can be addictive.

Neuropathic agents. This group of drugs act on a different pain gateway to the other medications above. They are very useful as adjuncts to the painkillers above to help optimise pain control.

Examples include gabapentin and pregabalin

For patients who are hospitalised with their rib fractures other modalities used include Patient controlled analgesia (PCA). This provides an intravenous source of analgesia (most commonly an opioid such as morphine or fentanyl) which is provided from a bedside pump which is activated to provide a specified dose of the painkiller by the patient pressing a button. The pump has a self locking mechanism which will ensure the next dose is available at the next safe interval.

Neuraxial blocks (eg thoracic epidural). These methods of pain control involve the insertion of fine catheters into spaces which contain nerves or nerve roots. Analgesic agents are then infused through the catheter to provide pain relief.

One of the consequences of multiple displaced rib fractures (4 or more) can be uncontrollable pain despite the above methods. Uncontrolled pain can lead to shallow, fast breathing and an inability to cough.

With persistent fast, shallow breathing the respiratory muscles which make the thorax to expand and contract can tire which leads to respiratory failure.

In this situation patients may require assistance with their ventilation. There are two main modes of assisted ventilation - non-invasive ventilation and invasive ventilation.

Non-Invasive ventilation is where the patient is awake and spontaneously breathing. A tight fitting mask is applied to the face. This mask is connected to a machine at the side of the bed which provides positive pressure to help the patient to breath. The two main types are CPAP (continuous positive airway pressure) and BiPAP (bilevel positive airway pressure).

Invasive ventilation is where a patient is sedated, anaesthetised and a mechanical ventilator supports their ventilation.

Surgery

In select cases surgery for rib fractures is indicated. Rib fractures suitable for acute surgery normally have both a particular fracture pattern and fracture distribution in combination with either/and/or uncontrollable pain, impending or established respiratory failure, those already being invasively ventilated, or severe chest wall deformity with impaired breathing mechanics.

• Flail chest
• Multiple rib fractures

Surgery for rib fractures requires an open incision, with some splits of underlying muscles, and exposure of the rib fractures. The rib fractures are then reduced back into their more natural position if they have displaced and they are held in place (fixed) with small titanium plates and screws.