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Upper extremity fractures account for more than half of all pediatric fractures1 and only 7% of geriatric fractures.2 The annual incidence of upper extremity fractures in the United States is 67.6 fractures per 10,000 persons.3 The most common shoulder girdle fractures occur in the proximal humerus, with fractures of the clavicle being second most prevalent. The annual incidence of proximal humeral fractures is 83.0 events per 100,000 persons,4 while clavicle fractures account for 24.4 injuries per 100,000 person years.5 Scapular fractures account for 13 fractures per 100,000 women and 37 fractures per 100,000 men. Glenoid fractures are rarer and account for 10% of scapular fractures with an overall prevalence of 0.1%.6
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Eighty percent of clavicle fractures occur within the middle third, while 15% involve the distal third, and 5% involve the proximal third.7 Distal clavicle fractures can be subclassified into three groups. Type I refers to a clavicle fracture distal to the coracoclavicular (CC) ligament with the ligament remaining intact. Group II refers to a clavicle fracture distal to the CC ligament with (IIB) or without (IIa) disruption of the CC ligament. Type III distal clavicle fractures refer to a fracture with intra-articular extension (Fig. 30–1).
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Trauma accounts for the most common etiology of clavicular fractures. Translational force from the lateral shoulder, falling on an outstretched hand, and direct contact with the clavicle may all lead to fracture. Less common causes include childbirth in the neonate, malignancy, and radiation therapy.8 In rare cases, stress fractures of the clavicle can be seen. Case reports typically center on gymnasts or weight lifters.
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A clavicle radiograph series is used for diagnosis. This series includes an anteroposterior (AP) view of the clavicle, acromioclavicular (AC) joint, and sternoclavicular (SC) joint, as well as an AP view with 15 degrees of cephalad angulation9 (Fig. 30–2). Computerized tomography (CT) scans can be performed in instances of equivocal radiographs or in cases of fracture near the AC or SC joint.
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