Gerdy’s Tubercle

Plain radiographs provide many indications suggestive of acute ACL rupture avulsion fracture of the lateral tibial plateau, or Segond fracture, which is in fact an injury to the lateral joint capsule, avulsion of the Gerdy s tubercle and a lateral notch lesion, which is a compression fracture of the lateral femoral condyle of more than 2 mm seen on lateral radiograph. A tibial rim lesion on the posterolateral lip of the lateral tibial plateau can also be found alone or associated with the lateral notch lesion and is termed a kissing contusion. Joint effusions can also be detected on simple radiographs (Fig. 20.6). 

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