Fracture, Clavicle

Author: Amir Estephan, MD,, Resident Physician, Department of Emergency Medicine, Kings County Hospital Center, Brooklyn
Coauthor(s): Robert J Gore, MD, Clinical Assistant Professor, Attending Physician, Assistant Residency Director, Department of Emergency Medicine, Kings County/State University of New York Downstate Hospital
Contributor Information and Disclosures

Updated: Sep 28, 2010

Print ThisEmail This

Overview
Differential Diagnoses & Workup
Treatment & Medication
Follow-up
Multimedia
References
Keywords
Information from Industry
Significant BMD increases at the spine and hip
Postmenopausal osteoporosis treatment showed significant BMD increases.
Learn more Introduction
Background
The clavicle is an oblong bone that connects the shoulder girdle to the trunk. It provides support and mobility for upper extremity function. Clavicle fractures account for 5% of all fractures and nearly half of significant injuries to the shoulder girdle. They are the most common of all childhood fractures.

Anatomically, the acromioclavicular and coracoclavicular ligament attach the clavicle to the scapula laterally. The sternoclavicular and the costoclavicular ligaments anchor the clavicle medially. The sternocleidomastoid and the subclavius muscles also have points of attachment to the clavicle. The clavicle also protects the adjacent brachial plexus, lung, and blood vessels.

Pathophysiology
Clavicular fractures are classified mechanistically and anatomically into 3 types. Approximately 80% of clavicle fractures occur in the middle third (class A), 15% involve the distal or lateral third (class B), and less than 5% involve the proximal or medial third (class C). The anatomy of the clavicle with potential fracture sites marked is shown in the image below.






Anatomy of the clavicle indicating potential fracture sites.
[ CLOSE WINDOW ]Anatomy of the clavicle indicating potential fracture sites.

Most class A fractures occur medial to the coracoclavicular ligament, at the junction of the middle and outer thirds of the clavicle. The proximal fragment is typically displaced upward because of the pull of the sternocleidomastoid muscle. The usual mechanism of injury involves a direct force applied to the lateral aspect of the shoulder as a result of a fall, sporting injury, or motor vehicle accident. Class A fractures are shown in the images below.



Nondisplaced middle clavicle fracture.
[ CLOSE WINDOW ]Nondisplaced middle clavicle fracture.



Displaced fracture of middle clavicle.
[ CLOSE WINDOW ]Displaced fracture of middle clavicle.



Displaced middle clavicle fracture.
[ CLOSE WINDOW ]Displaced middle clavicle fracture.

Fractures of the lateral third (class B) result from a direct blow to the top of the shoulder. They occur distal to the coracoclavicular ligament and are classified further into 3 subtypes. Type I fractures are nondisplaced, and the coracoclavicular ligaments remain intact. Type II fractures are displaced, and there is associated rupture of the coracoclavicular ligament with the proximal clavicular segment typically pulled upward by the sternocleidomastoid muscle. Type III injuries involve the articular surface of the acromioclavicular joint.1
Fractures of the medial third (class C) occur as a result of a direct blow to the anterior chest. A diligent search for associated injuries should accompany all of these fractures because considerably strong forces are required to fracture this area of the clavicle.

Greenstick or buckle-type fractures are common in children. Most of these fractures are nondisplaced and heal uneventfully.


Frequency
International
The annual incidence rate of clavicular fractures is estimated to be between 30 and 60 cases per 100,000 population.2
Mortality/Morbidity
While the overwhelming majority of clavicle fractures are benign, associated life-threatening intrathoracic injuries are possible. Complications vary based on location of fracture (see Complications).

Sex
The male-to-female ratio is 2:1 for clavicle fractures.

Age
Clavicle fractures are the most common of all pediatric fractures. They can present in the newborn period, especially following a difficult delivery, and nearly half of all clavicle fractures occur in children younger than 7 years. A large peak incidence occurs in males younger than 30 years due to sports injuries. A smaller peak of incidence occurs in elderly patients in whom the injury is sustained during low-energy falls and is related to osteoporosis.2
Clinical
History
•The patient typically reports a fall onto an outstretched upper extremity, a fall onto a shoulder, or direct clavicular trauma.
•Pain, especially with upper extremity movement
•Swelling
Physical
•The affected extremity is held close to the body, adducted against the chest wall, supported by the other extremity.
•Inferior and anterior displacement of the shoulder occurs secondary to loss of support.
•Tenderness
•Crepitus
•Edema
•Deformity
•Ecchymosis, especially when severe displacement causes tenting of skin
•Bleeding from open fracture (rare)
•Decreased breath sounds on auscultation, indicating possible pneumothorax
•Decreased pulses or evidence of decreased perfusion on vascular examination, suggesting vascular compromise
•Diminished sensation or weakness on distal neurovascular examination, suggesting neurologic compromise
•Nonuse of the arm on the affected side in neonates
Causes
•Fall onto a shoulder or an outstretched upper extremity
•Direct blow to the clavicle
More on Fracture, Clavicle