Gallus A, Raman K, Darby T.
Venous thrombosis after elective hip replacement - the influence of preventive
intermittent calf compression and of surgical technique.
Br J Surg 1983 Jan;70(1):17-9

The effect of preventive intermittent calf compression on the incidence,
distribution and extent of venous thrombosis after elective hip replacement was
examined by randomized trial in 90 patients who were screened for postoperative
thrombosis with 125I-fibrinogen leg scanning and impedance plethysmography,
followed by routine venography on the seventh postoperative day. Venography
showed that leg compression reduced the incidence of calf vein thrombosis from 45
per cent (21/47) in untreated patients to 16 per cent (7/43) (P less than 0.005),
but not that of proximal (i.e. popliteal or femoral) vein thrombosis, which
occurred in 23 per cent of treated and 26 per cent of untreated patients.
However, proximal vein thrombosis appeared to be less extensive in treated
patients. Proximal vein thrombosis was found in 40 per cent of patients who had
hip replacement by a modified Charnley technique (17/43 patients), and 9 per cent
of patients in whom a posterior surgical approach was used (4/43 patients) (P
less than 0.005), strongly suggesting that surgical technique may influence the
proximal vein thrombosis rate after elective hip replacement.