Title: Radiology in Slipped Capital Femoral Epiphysis<br/>Author: Brian Corwell<br/><a href='http://umem.org/profiles/faculty/294/'>[Click to email author]</a><hr/><p align="center">
        <strong>Slipped Capital Femoral Epiphysis (SCFE)</strong></p>
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                Progressive, posterior medial displacement (slipping) of the proximal femoral epiphysis
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                                Complicated by AVN and premature physis closure</li>
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        <a href="http://www.raymondliumd.com/images/SCFE%20illustrated%20and%20cropped.jpg">http://www.raymondliumd.com/images/SCFE%20illustrated%20and%20cropped.jpg</a></p>
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        <strong>Early Diagnosis:</strong></p>
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                Allows best chance for intervention and good functional outcome</li>
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                Subtle and difficult with X-ray</li>
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                Classic teaching is Klein’s line</li>
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        <strong>Klein’s Line on AP view</strong></p>
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                A line drawn from the superior aspect of the femoral neck will not intersect the femoral head epiphysis</li>
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                Modified line
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                                >2mm difference in width lateral to line between each side</li>
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        <a href="https://pedemmorsels.com/wp-content/uploads/2018/01/Slipped-Capital-Femoral-Epiphysis-3.png">https://pedemmorsels.com/wp-content/uploads/2018/01/Slipped-Capital-Femoral-Epiphysis-3.png</a></p>
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        <strong>Another virtual line may assist in diagnosis</strong></p>
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        <strong>S-sign</strong></p>
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                The <strong>S</strong>-<strong>sign</strong> is a curvilinear line drawn on the inferior margin of the proximal femoral head neck junction along the proximal femoral physis.</li>
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                 Discontinuity or an abrupt sharp turn are abnormal</li>
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        <a href="https://images.squarespace-cdn.com/content/v1/562149a6e4b0bca6fa53cb35/1530197888065-AOF0LA079Y81Q6M89RJU/ke17ZwdGBToddI8pDm48kE2XMWnCJSZ3ROkmIxQ7DdsUqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcIZH9X6Fb-UKi0lvZd9RVmtFt1P_lj4JzgsdTxe78uiejbzfgXQaCWxJNArJhpf7P/Screen+Shot+2018-06-26+at+10.09.17+AM.png?format=1500w">https://images.squarespace-cdn.com/content/v1/562149a6e4b0bca6fa53cb35/1530197888065-AOF0LA079Y81Q6M89RJU/ke17ZwdGBToddI8pDm48kE2XMWnCJSZ3ROkmIxQ7DdsUqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcIZH9X6Fb-UKi0lvZd9RVmtFt1P_lj4JzgsdTxe78uiejbzfgXQaCWxJNArJhpf7P/Screen+Shot+2018-06-26+at+10.09.17+AM.png?format=1500w</a></p>
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        <strong>Klein's line and S-sign</strong></p>
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                A group of 20 orthopedic surgeons, radiologists, and pediatricians viewed 35 radiographs of SCFE using Klein's line on the AP view and the S-sign on frog-leg lateral view to make the diagnosis. </li>
</ul>
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                Overall diagnostic accuracy was better with the S-sign than Klein's line, 92% vs 79%.
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                                Sensitivity of the S-sign was 89%, specificity 95%. </li>
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                                Sensitivity of Klein's line was 68%, specificity 89%. </li>
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</ul>
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                Combined S-sign + Klein's line sensitivity was 96%, specificity 85%.</li>
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        Consider adding both of these virtual lines/signs to your review of the pediatric hip plain film</p>
<fieldset><legend>References</legend>

                <p>
        Rebich et al., 2018. The S Sign: A New Radiographic Tool to Aid in the Diagnosis of Slipped Capital Femoral Epiphysis. J Emerg Med. </p>
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