Prepatellar bursitis

US findings of acute prepatellar bursitis reflect the underlying pathology. In an acute gout attack, US detects an anechoic intrabursal effusion, whereas in post-traumatic bursitis the blood filling the bursa... 

Fig. 14.50a,b. Acute prepatellar bursitis. Transverse a gray-scale and b color Doppler 12-5 MHz US images over the anterior aspect of the patella demonstrate marked thickening of the prepatellar soft-tissues white arrows) within which a small fluid collection can be seen. Color Doppler imaging reveals an increased vasculature arrowheads) within the thickened bursal walls reflecting inflammatory hyperemia... 

In terms of clinical relevance, disorders related to the extensor mechanism are the leading pathology of the anterior knee. Other conditions in vdiich US plays a diagnostic role include prepatellar and infrapatellar bursitis, some bone and positional abnormalities of the patella and the so-called mediopatel-lar plica syndrome. 

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