Kager's sign; an underestimated radiographic feature in detecting acute Achilles tendon rupture: A report on two cases

The Achilles tendon rupture is the most common tendon rupture in the lower extremity. Although magnetic resonance imaging (MRI) is accepted as the gold standard imaging approach for diagnosing the Achilles tendon rupture, radiography should be encouraged which is less expensive and more accessible and can simultaneously evaluate bone, air, and soft tissue. Kager’s triangle which is observed on lateral ankle radiography is important in evaluating the pathologies of Achilles tendon. We reported two cases of traumatic Achilles tendon rupture identified on radiographic imaging with a positive Kager's sign in emergency department and surgically confirmed. Both patients received early surgical repair and recovered completely. The clinical use of Kager's sign, which facilitates the radiological diagnosis of Achilles tendon rupture in the early period especially in emergency departments, should be increased and further studies should be conducted on its diagnostic value.

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