The painful swollen calf. A comparative evaluation of four investigative techniques.

Complications of popliteal cysts may closely mimic the clinical features of a deep venous thrombosis. We assessed the sensitivity and specificity of the non-invasive procedures of radionuclide venography and popliteal space ultrasound examination compared with those of contrast venography and arthrography, respectively, and then prospectively studied 23 non-surgical patients with acutely painful, swollen calves to determine the utility of these techniques. The cause of this symptom was popliteal cyst complications in 10 patients, deep venous thrombosis in seven patients, and both conditions in two patients. Radionuclide venography was highly reliable and ultrasound examination was specific but only moderately sensitive in these studies. The painful, swollen calf may be investigated adequately in most cases by means of noninvasive invasive techniques; contrast venography and arthrography should be reserved for only a minority of patients.