Rockwood Children CH19

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CHAPTER 19 • Clavicle and Scapula Fractures and Acromioclavicular and Sternoclavicular Injuries

SIGNS AND SYMPTOMS OF MIDSHAFT CLAVICLE FRACTURES

younger, children abused had an incidence of clavicle fractures of approximately 4% compared with only about 1% in the control group. 119 School age clavicle fractures occurring in children are typi- cally the result of a fall where the child sustains a lateral compres- sive force to the shoulder. 140 Typical activities include falls off of playground equipment, falls from bicycles, and during sporting activities. Alternatively, a direct blow to the clavicle can lead to fracture in a child; however, this mechanism is less common. The common fall onto an outstretched hand does not typically transmit enough force to the clavicle to sustain a fracture, 67 but is another reported mechanism of injury in some cases. Adolescents sustain clavicle fractures due to similar mecha- nisms as school age children as well as due to high-energy mech- anisms or competitive athletics. Motor vehicle and all-terrain vehicle (ATV) accidents are common high-energy mechanisms in adolescents that can result in either isolated clavicular frac- tures or clavicular fractures associated with polytrauma similar to adults. 77,121 High-level competitive athletes also commonly sus- tain clavicle fractures due to collision sports, such as football, or much less commonly, due to repetitive, high-intensity training, leading to a stress fracture, though this has only emerged in case reports. 1 Specific sporting activities that can lead to stress frac- tures include rowing, diving, baseball, and gymnastics, among others. 1,153,160 The proposed mechanism leading to a clavicular stress fracture is excessive cyclic scapular protraction and retraction leading to clavicular fatigue. 1 Excessive motion at the sternocla- vicular and acromioclavicular (AC) joints transfers the forces to the clavicle itself, with the end result being these forces exceed- ing the ultimate tensile strength of the clavicle. 1 This most com- monly occurs in athletes who rapidly increase their training program. Injuries that are associated with clavicle fractures depend on the age of the child and violence of trauma with the fracture. Neo- nates can have a concomitant neonatal brachial plexus palsy. The most common type of neonatal brachial plexus palsy is an injury affecting C5 and C6 (Erb’s palsy) or C5, C6, and C7 with resultant limited shoulder movement, elbow flexion, forearm supination, and wrist extension. 48 Differentiation between a pseudopalsy, the child not moving their arm secondary to the clavicle fracture itself, and a concomitant l brachial plexus birth palsy can be made by 3 to 4 weeks of age, as the pain from the fracture will be markedly decreased. Toddlers who sustain clavicle fractures as a result of nonaccidental trauma are likely to sustain concomitant fractures, such as fractures of the rib, tibia/fibula, humerus, or femur, intracranial bleeding, eye con- tusions, retinal hemorrhage, and burns. 28,119 Finally, adolescents involved in high-energy mechanisms of injury can have asso- ciated polytrauma including injury to surrounding structures or vital organs. Concomitant rib fractures, scapula fractures, pneumothorax, brachial plexus injury, or subclavian vessel injury may be present. 67 Abdominal, head, spine, and/or lower extremity trauma can also occur. INJURIES ASSOCIATED WITH MIDSHAFT CLAVICLE FRACTURES

Clavicle fractures in neonates commonly present after difficult deliveries with decreased active movement about the shoulder region, crying upon passive movement of the shoulder and entire upper extremity, swelling, crepitation, and an asymmetrical bony contour. The Moro (startle) reflex (a newborn reflex in which a noise or sudden movement causes the baby to extend their neck, arms, and legs followed by pulling the arms and legs back in) may be decreased as well. 63 Presence of limited digit motion or Horner syndrome (ptosis, miosis, and anhydrosis) indicates the presence of a more serious concomitant brachial plexus birth palsy with injury affecting the lower portions of the brachial plexus. Toddlers who sustain clavicle fractures associated with sus- pected abuse should undergo a complete head-to-toe survey, as if they were a trauma patient, looking for concomitant injuries and/ or signs of abuse. This includes a thorough neurologic evaluation, an ophthalmologic examination, and a skeletal survey to look for corner fractures or additional fractures in various stages of healing. Examination of an older child or adolescent with a clavicle fracture includes looking for deformity, swelling, and ecchymo- sis about the affected clavicle. Any tenting of the skin (Fig. 19-2) or open wounds should be noted. In addition, one should look at the lateral aspect of the shoulder for an abrasion or erythema, as this is most commonly the site of impact. Inspection may also demonstrate some drooping of the involved side as the scapula appears internally rotated and the shoulder appears shortened compared with the contralateral side. If significant swelling is present, this may be difficult to recognize. 67 Pain about the entire shoulder girdle is typically present; however, significant tenderness to palpation is present overly- ing the fracture itself. Crepitus, with palpation or any attempt of active or passive range of motion, may be present. As noted above, concomitant injury to the brachial plexus may occur, especially in the medial cord-ulnar nerve because of its location adjacent to the middle third of the clavicle. Therefore, a thor- ough neurologic examination is required for all patients who sustain clavicular fractures. This includes assessing motor and sensory function throughout the entire upper extremity. It may be difficult to have a child in pain perform certain functions necessary to complete the neurologic evaluation; however, it is imperative to be patient and repeat the examination as often as necessary to obtain the necessary information. Because of the location of the subclavian vessel, a thorough vas- cular examination is also necessary, especially in patients involved in high-energy mechanisms of injury. The vessel can spasm, have a thrombosis from blunt trauma, or rarely have a penetrating injury. Assessment of the radial pulse should be symmetric and if there is any concern for injury of the vessel, further diagnostic evaluation with advanced imaging should be performed.

IMAGING AND OTHER DIAGNOSTIC STUDIES FOR MIDSHAFT CLAVICLE FRACTURES

Initial imaging of a suspected clavicle fracture includes plain radiographs of the clavicle in two projections. Typically, a standard anteroposterior (AP) radiograph and a cephalic tilt