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Clavicle fractures most commonly occur in people under the age of 25 and those over the age of 70.

Clavicle fractures are commonly known as a breaking of the collarbone, and they are usually a result of injury or trauma. The most common type of fracture occurs when a person falls vertically onto the shoulder or with an outstretched hand. A direct hit to the collarbone can also cause a break. In most cases, the direct hit occurs from the joint side towards the body side of the bone. The muscles involved in clavicle fractures include the deltoid, trapezius, subclavius, sternocleidomastoid, and sternohyoid. The ligaments involved include the conoid ligament and trapezoid ligament. Incidents that may lead to a clavicle fracture include automobile accidents, biking accidents (especially common in mountain biking), vertical falls on the shoulder joint, or contact sports such as football, rugby, hurling, or wrestling. It is most often fractured in the middle third of its length which is its weakest point. The lateral fragment of the clavicle during a fracture is depressed by the weight of the arm and is pulled downward by the strong abductor muscles of the shoulder joint, especially the deltoid. The part of the clavicle near the center of the body is tilted upwards by the sternocleidomastoid muscle. Children and infants are particularly prone to it. Newborns often present clavicle fractures following a difficult delivery. After fracture of the clavicle, the sternocleidomastoid muscle elevates the medial fragment of the bone. The trapezius muscle is unable to hold up the distal fragment owing to the weight of the upper limb, thus the shoulder droops. The adductor muscles of the arm, such as the pectoralis major, may pull the distal fragment medially, causing the bone fragments to override.

The clavicle is the bone that connects the trunk of the body to the arm, and it is located directly above the first rib. A clavicle is located on each side of the front, upper part of the chest. The clavicle consists of a medial end, a shaft, and a lateral end. The medial end connects with the manubrium of the sternum and gives attachments to the fibrous capsule of the sternoclavicular joint, articular disc, and interclavicular ligament. The lateral end connects at the acromion of the scapula which is referred to as the acromioclavicular joint. The clavicle forms a slight S shaped curve where it curves from the sternal end laterally and anteriorly for near half its length, then forming a posterior curve to the acromion of the scapula.

The basic method to check for a clavicle fracture is by an X ray of the clavicle to determine the fracture type and extent of injury. In former times, X rays were taken of both clavicle bones for comparison purposes. Due to the curved shape in a tilted plane X rays are typically oriented with ~15° upwards facing tilt from the front. In more severe cases, a computerized tomography (CT) or magnetic resonance imaging (MRI) scan is taken. However, the standard method of diagnosis through ultrasound imaging performed in the emergency room may be equally accurate in children.

Medication may be prescribed for pain. It is unclear if surgery or conservative management is superior. Antibiotics and tetanus vaccination may be used if the bone breaks through the skin; however, this is uncommon. Often, they are treated without surgery. In severe cases, surgery may be done.

The arm is usually supported by an external immobilizer to keep the joint stable and decrease the risk of further damage. The two most common types of fixation are the figure of eight splint that wraps the shoulders to keep them forced back and a simple broad arm sling (which supports the weight of the arm). The primary indication is pain relief. Type of sling used does not seem to affect the results as far as healing is concerned but patient satisfaction is lower with the figure of eight bandage. No difference in functional outcome has been reported between the two types of immobilization. Current practice for simple fractures without great displacement is generally to provide a sling, and pain relief, and to allow the bone to heal itself, monitoring progress with X rays every week or few weeks if necessary. Surgery is employed in 5–10% of cases. However, a meta analysis of 2 144 midshaft clavicle fractures supports primary plate fixation of completely displaced midshaft clavicular fractures in active adult patients. If the fracture is at the lateral end, the risk of nonunion is greater than if the fracture is of the shaft.

Healing time varies based on age, health, complexity, and location of the break, as well as the bone displacement. For adults, one to several weeks of sling immobilization is normally employed to allow for pain relief, initial bone and soft tissue healing; teenagers require slightly less, while children can often achieve the same level in two weeks. During this period, patients may remove the sling to practice passive pendulum range of motion exercises to reduce atrophy in the elbow and shoulder, but they are often minimized to 15–20° off vertical. Depending on the severity of fracture, a person can begin to use the arm if comfortable with movement and no pain results. The final goal is to be able to have full range of motion with no pain; therefore, if any pain occurs, allowing for more recovery time is best. Depending on severity of the fracture, athletes involved in contact sports may need a longer period of rest to heal to avoid refracturing bone. A person should be able to return unrestricted to any sports or work by 3 months after the injury.

Clavicle fractures occur at 30–64 cases per 100,000 a year and are responsible for 2.6–5.0% of all fractures. This type of fracture occurs more often in males.