Fractures of the Clavicle

Anatomy and mechanism.
The clavicle, otherwise known as the collarbone, is the main stabilizer
between the axial (via the sternoclavicular joint) and the appendicular
(via the acromioclavicular joint) skeleton. Any force absorbed by the
upper extremity transmits to the thorax through the clavicle. This
fact, in addition to its superficial location, explains why it is
vulnerable to injury. In fact, it has been estimated to be the most
commonly fractured bone (1,2).

Most frequently, clavicle fractures result from a blow
to the shoulder region such as during a fall to the turf, though they
also may result from a direct hit to the collarbone. These fractures
are most commonly seen in children and young adults (1),
although they are diagnosed with increasing frequency in later decades
where more active lifestyles are taking place in the context of
epidemic osteoporosis.

Classification.
Allman classified these fractures according to whether they were
proximal, middle, or distal one third injuries and noted that the
middle one-third fracture was by far the most common (3).
The distal one-third clavicle fracture should be distinguished further
as to whether it is intraarticular or extraarticular and whether or not
it is displaced, which would imply disruption of the coracoclavicular
ligaments (4).

History and physical exam.
Pain and deformity localized to the clavicle provide the most typical
presentation. Frequently, ecchymosis and tenting of the skin are
recognized. The typical deformity in the common middle third fracture
is caused by the proximal (medial) fragment bone spike being pulled by
the sternocleidomastoid muscle, which inserts on the proximal clavicle.
The deformity is accentuated by the weight of gravity on the upper
extremity pulling downward on the distal (lateral) fragment.

Physical exam will frequently detect bony crepitance and
should include inspection of the skin for punctures or lacerations
consistent with an open fracture. As the clavicle is directly anterior
to the brachial plexus and the subclavian artery, exam should also
include neurovascular assessment, particularly in injuries associated
with high-energy mechanisms.

Radiographs.
A standard anteroposterior view of the clavicle usually confirms the
diagnosis of a fracture. Comminution and displacement should be
described. The degree of overriding of the fracture fragments should be
noted as well since impaction forces to the lateral forequarter can
cause medialization of the shoulder. This is an important variable in
deciding on treatment. Oftentimes, in the setting of polytrauma, a
chest x-ray provides the initial radiographic diagnosis. Surrounding
structures such as the scapula and ribs should be inspected for injury
as well.

Nonoperative.
The vast majority of clavicle fractures should be treated
nonoperativley. Extraarticular fractures displaced less than 1 cm are
treated with a simple sling or sling-and-swathe immobilizer for
comfort. A figure-of-8 strap may be used to maintain the shoulder in a
retracted position to theoretically improve alignment. This technique
may be most useful for children, in which case care must be

taken
not to snug it too tightly, which can compromise skin and compress the
brachial plexus. Studies do not seem to suggest, however, that there is
any difference in shoulder function, range of motion, or residual
deformity between the use of a sling or a figure-of-8 strap (5).

Intraarticular distal clavicle fractures most often also
warrant nonoperative treatment if the coracoclavicular ligaments are
intact and there is not much displacement of the proximal clavicular
shaft. In the case of intraarticular clavicle fractures, the patient
should be warned of the possibility of arthritic symptoms if there is
stepoff or comminution at the acromioclavicular joint. This outcome can
be treated on a delayed basis with distal clavicle resection. In
children, a couple of weeks of relative immobilization is all it takes
before calus begins to provide the splinting necessary for healing of
the bone ends. In adults, a month of such immobilization will provide
the same relief.

Operative. There are several indications for operative management of clavicle fractures.

Follow-up.
Patients should be followed up in the office at 2 and 4 weeks after the
injury to check radiographs to make sure that further displacment has
not occurred. They need reassurance that discomfort, crepitance, and
deformity are expected during this phase of healing. After this
juncture, passive and gentle active range of motion should be
encouraged, as well as light lifting, guided by the patient’s symptoms.
Most often, good function has been restored by 3 months post injury, at
which time restrictions can usually be lifted. Radiographic healing
should be nearly complete by this juncture but can take months,
particularly in the elderly.

Complications.
Patients should be counseled from the beginning that they should
anticipate a lump in the region of the fracture if treated
nonoperatively. Reported nonunion rates are in the range of 0.1% to
0.8% (2,6,10), though certain risk factors such as displaced distal fractures and clavicle fractures in the elderly have been identified (10).