Ryan MG, Westrich GH, Potter HG, Sharrock N, Maun LM, Macaulay W,
Katkin P, Sculco TP, Salvati EA.
Effect of mechanical compression on the prevalence of proximal deep venous
thrombosis as assessed by magnetic resonance venography.
J Bone Joint Surg Am 2002 Nov;84-A(11):1998-2004

The Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA.

BACKGROUND: Patients have been shown to be at greater risk for deep venous
thrombosis, particularly proximal thrombosis, after total hip arthroplasty.
Proximal thrombi are more likely to develop into pulmonary emboli than are distal
thrombi. The purpose of this randomized, prospective study was to compare the
prevalence of pelvic and proximal lower-extremity deep venous thrombosis after
primary total hip arthroplasty between patients treated with an impulse
mechanical compression device for prophylaxis and those treated with prophylactic
stockings. METHODS: One hundred patients were evaluated, with use of magnetic
resonance venography, for proximal deep venous thrombosis after total hip
arthroplasty. Fifty patients were treated with a mechanical compression device on
both lower extremities, and the other fifty patients received only prophylactic
stockings. Both groups of patients received hypotensive epidural anesthesia and
325 mg of aspirin twice a day. RESULTS: Overall, proximal deep venous thrombi
were found in 15% of the 100 patients. Of the fifty patients treated with
mechanical compression, 8% (four) had a positive venogram. Of the fifty control
patients, 22% (eleven) had a positive venogram (p < 0.05). However, overall the
rate of occlusive thrombi was 6% (six) compared with an overall rate of
nonocclusive thrombi of 9% (nine). The rate of occlusive thrombi was 2% (one of
fifty) in the study group and 10% (five of fifty) in the control group (p =
0.04). CONCLUSIONS: On the basis of this study, we concluded that patients
managed with total hip arthroplasty benefit from a reduction in the rates of
femoral and pelvic deep vein thrombosis when they are treated with hypotensive
epidural anesthesia, mechanical compression, and aspirin and are subsequently
assessed with magnetic resonance venography.