Your collarbone connects the shoulder blade to the upper part of your breastbone. The medical name for this bone is the clavicle. At the outer end it makes a joint known as the acromioclavicular (AC) joint. The bone acts as protection to the nerves and blood vessels below as they transit from the neck to the arm.
It also helps support co-ordinated movement of the shoulder blade. However, the importance of this is dependent on natural posture and the strength of shoulder blade muscles. Some people are born without a collar bone and, because their body adapts to this variation, they tend not experience any shoulder problems or weakness in adulthood.
Clavicle fractures tend to be caused by falling onto your outstretched hand or shoulder, or getting injured playing sport or in a cycling or road traffic accident. These injuries can occur in anybody at any age but are particularly common in young and middle-aged adults. New-born babies can also fracture their collarbone when passing through the birth canal, but their injuries heal extremely quickly. The bone can fracture at any point its length. Middle third fractures are most common, followed by the outer third.
AC joint dislocations
Acromioclavicular (AC) joint dislocations are also common, accounting for around 9% of all shoulder girdle injuries. Also known as an AC separation, these injuries tend to be caused by a direct blow to the shoulder or falling heavily onto the shoulder. They occur most often in sportspeople and are more common in men than women. Depending on the extent of the separation, you may sustain damage to the acromioclavicular ligaments or coracoclavicular ligaments or both.
Symptoms of a collarbone or AC injury
You may experience a range of symptoms if you have fractured your collarbone or injured your AC joint, most commonly:
- Pain that is worse when you move your shoulder. If you have an AC injury it is usually over the AC joint or upper back muscle (trapezius).
- Swelling, tenderness and/or bruising.
- Stiffness or being unable to move your shoulder.
- A grinding noise when you try to move your shoulder.
- Numbness and weakness of the elbow and hand if a nerve injury has occurred at the same time (fortunately rare).
Diagnosis of collarbone or AC injuries
It is important to have a proper diagnosis as AC injuries and clavicle fractures share similar symptoms and it can be hard to distinguish one from the other.
The doctor will carry out a physical examination to check for any swelling, tenderness or deformity. Ultimately, an X-ray will be required to confirm the diagnosis. For subtle or unusual patterns of injury you may also be referred for a CT scan or an X-ray of the other side to compare.
Do you need surgery?
Most clavicle fractures will eventually heal by themselves. However, if it is severely fractured it may take a long time to heal, may not heal fully, or may heal with an overlap which weakens the shoulder. Healing with up to 2cm of overlap may be acceptable if you wish to avoid surgery. It is now possible to predict the chance of the fracture healing by 6, 12 and 26 weeks, dependent on the severity of the fracture, as well as your age and sex. Smoking will slow down healing and increase the chance of it not healing at all.
Traditionally, AC joint dislocations were graded according to the distance of joint separation on an X-ray. Complete separations were treated with surgery. More recently it has been shown that an operation is not necessary in the vast majority of cases, for the same reasons that children born without a collar bone usually have excellent shoulder function. Rather than relying on X-rays alone, it is now known that examination by a specialist a few days after the injury to assess shoulder blade position and strength is the most important determinant of the need for surgery.
Equally, if the pain and discomfort from the injury does not settle significantly in the first three weeks after injury this is also a strong indicator that surgery may be required.
Your doctor will discuss with you the most effective treatment plan in your individual case.
Initial treatment of a fractured collarbone
The normal initial approach to treating a fractured collarbone is to immobilise the broken bone by wearing an arm sling. In the case of newborns and pre-adolescent children, collarbone fractures normally heal with just pain control and careful handling.
In addition to wearing a sling, you will need to take painkillers and anti-inflammatories. If the pain is severe you may need to take prescription painkillers for a few days. Applying ice to the affected area can reduce swelling and ease pain. If surgery has not been recommended, when the pain has settled and the injury has started healing you will normally need to do exercises recommended by a physiotherapist to reduce stiffness in your shoulder and restore flexibility and muscle strength.
If you need to undergo surgery to repair a clavicle fracture you may be offered an open reduction internal fixation (ORIF) procedure. This involves making an incision in the skin above the affected area and realigning the bones using a titanium plate and screws to hold the bones together while they heal. The plate is strong enough to support the bone early on, so that you can make a speedy recovery to full motion and activity.
Many people want the plate to be removed after a year or so because the clavicle is a very superficial bone (i.e. the plate is just under the skin and can cause some discomfort when wearing a strap over the shoulder). When surgery is indicated for an AC joint dislocation a number of surgical techniques are described, each have pros and cons. Surgeons generally have their own preference according to what they find most successful and reliable.
If surgery occurs within four weeks of injury then strong suture and/or tape is used to hold the collar bone in place whilst the necessary ligaments heal around it. If surgery is more delayed the ligaments lose their potential for natural healing and therefore the surgeon will use synthetic or donated ligament to compensate. The arm is normally rested in a sling for four weeks or so, followed by graduated physiotherapy to restore movement and strength. Contact sports are to be strictly avoided for six months.
Generally speaking, surgery for a collarbone injury has a low complication rate. The most common are an infection (1-2%), failure of bone or ligament healing (<5%) and lung, nerve and blood vessel injury (much less than 1%). However, almost 100% of patients do have persistent numbness on the upper chest below their scar, which can reach as far as the nipple in a handful of cases.
How we help
Orthopaedic surgeons will always tailor-make treatments to the needs of individual patients and will discuss all of the treatment options with you fully so you can reach a shared decision about the best way forward.
If you have a fractured collarbone or AC injury, contact us to discuss the most appropriate treatment for you.