Rockwood Children CH19

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

to gain additional information, CT scan is recommended over MRI scan to evaluate acute injuries because of its speed and availability.

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CLASSIFICATION OF STERNOCLAVICULAR FRACTURE–DISLOCATIONS

Sternoclavicular dislocations are classified based on the direc- tion of displacement, anterior or posterior, as well as the chro- nicity of the injury, acute or chronic. The injury needs to be defined as a dislocation (displacement between the epiphysis and the sternum) or a fracture (displacement through the phy- sis with the epiphysis still articulating with sternum). In addi- tion, a sprain, rather than a true dislocation, may occur leading to subluxation. OUTCOME MEASURES FOR STERNOCLAVICULAR FRACTURE–DISLOCATIONS No specific outcome scores exist that specifically evaluate ster- noclavicular joint injuries. Results reported have assessed sub- jective complaints of pain, recurrence of instability, return to function, and utilization of adult shoulder outcome measures, such as the ASES score, the simple shoulder test, and Rockwood scores.

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affected side will appear superiorly displaced, whereas in cases of posterior dislocation, the affected side will appear inferiorly displaced (Fig. 19-17). Despite these described plain radiographic views, the easi- est way to evaluate the sternoclavicular joint is with computed tomography (CT) scan which provides a three-dimensional view of the joint (Fig. 19-18). In addition to assessment of the sternoclavicular joint, one can evaluate the adjacent soft tissue structures including the esophagus, trachea, lungs, and bra- chiocephalic vessels. Distinction between a physeal fracture and a true dislocation may also be possible if the secondary center has ossified. Magnetic resonance imaging can also be utilized to evalu- ate the sternoclavicular joint as well as the surrounding soft tissues. The integrity of the costoclavicular ligaments and intra-articular disk may be possible. 55 Despite the potential C Figure 19-16.  ( Continued ) C: Schematic demonstrating a serendipity view of Rockwood. (Reprinted with permission from Waters PM, Bae DS, eds. Pediatric Hand and Upper Limb Surgery: A Practical Guide. 1st ed. Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams &Wilkins; 2012.)

PATHOANATOMY AND APPLIED ANATOMY RELATED TO STERNOCLAVICULAR FRACTURE–DISLOCATIONS

The sternoclavicular joint is a true diarthrodial joint compris- ing the medial clavicle and clavicular notch of the sternum. Thus, this joint is the only connection between the axial skel- eton and the upper extremity. However, less than 50% of the clavicular head articulates with the clavicular notch of the ster- num, resulting in little bony congruity. Stability is therefore provided by the multiple ligamentous and muscular attach- ments, including the sternocleidomastoid, pectoralis major,

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B

Figure 19-17.  A: Serendipity radiograph showing a left posteriorly dislocated sternoclavicular joint. Note that the affected side appears inferiorly displaced. B: CT scan of the same patient clearly showing the left posterior dislocation.