Seventy-five of 150 consecutive patients who underwent total knee
arthroplasty had routine physiotherapy and seventy-five had continuous
passive motion of the lower limb that had been operated on as well as
routine physiotherapy. A pulmonary embolus did not develop in any patient,
but about 40 per cent had thrombosis in the veins of the calf, whether
passive motion had been administered or not. Radiographically, the
deep-vein thrombosis was seen to extend into or proximal to the popliteal
vessel in 5 per cent of the patients in each group. Sex, age, obesity, or a
history of hypertension or diabetes did not influence the incidence of
venous thrombosis, but there was a higher incidence in patients in whom
cement was used for fixation of the total knee components, irrespective of
the use of continuous passive motion of the limb.