Standard ankle radiographs may reveal a normal-appearing ankle but may also show subtle signs of injury such as a fleck of bone off the posterior tubercle of the tibia. Radiographs may also reveal chronic injury to the syndesmosis with calcification of the ligaments and interosseous membrane. Diastasis of the syn-desmosis is indicated when there is no malleolus fracture and the mortise is widened medially more than 4 mm. This can be variable, and comparison radiographs may be necessary. Another method is to use the amount of overlap of the fibula and tibia of 5 mm on the anteroposterior view or 1 mm on the mortise view. The tibiofibular clear space is the distance between the fibula and the incisura of the tibia 1 cm proximal to the plafond. This normal distance has been found by several studies to be fairly consistent at about 4 mm.12-14
If there are clinical findings of syndesmosis injury and standard radiographs are negative, external rotation stress radiographs are indicated. These can be difficult to interpret and may be limited by patient pain, but if there is obvious widening, it is a useful test. A bone scan may be a way to diagnose injuries that are not diagnosed with stress radiographs limited by patient pain. Magnetic resonance imaging is also very sensitive in detecting ligamentous injury and is becoming more common in helping to determine return to play and prognosis in high-demand athletes. Certainly, if there is any widening of the mortise on any view, the entire fibula must be visualized on radiographs (Fig. 68-7).
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Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.