This is a timely study. The orthopaedic community has been investigating the use of treatment methods other than the chemoprophylactic use of low-molecular-weight heparin and full-dose warfarin1,2. This randomized study clearly shows the efficacy of mechanical prophylaxis with use of intermittent pneumatic compression for both elective procedures and emergency procedures for the treatment of trauma. The use of intermittent pneumatic compression and low-molecular-weight heparin (certoparin) provided highly significant (p = 0.007) improved protection against deep venous thrombosis as compared to low-molecular-weight heparin alone. Although the American College of Chest Physician guidelines for total hip replacement do not recommend the use of intermittent pneumatic compression after total hip replacement except in patients who are at a high risk of increased bleeding3, the study by Eisele et al. did show a benefit because patients who had total hip replacement and were managed with low-molecular-weight heparin and intermittent pneumatic compression had no deep venous thrombosis.
The prevalence of deep venous thrombosis was so low with intermittent pneumatic compression and low-molecular-weight heparin (four of 901, 0.44%) that we agree with the authors that they should compare the use of low-molecular-weight heparin to the use of intermittent pneumatic compression alone. Hooker et al.4, in their study of intermittent pneumatic compression and aspirin after primary and revision total hip arthroplasty, reported a higher rate of deep venous thrombosis (twenty-three [4.6%] of 502 hips) than the rate that was reported in this study but also reported no deaths from pulmonary embolism. The use of intermittent pneumatic compression along with aspirin is the foundation of the multimodal treatments advocated for total hip replacement1,5-7 and total knee replacement8. These treatments differentiate patients who are at low risk and patients who are at high risk for venous thromboembolism and reserve the use of chemoprophylaxis with warfarin or low-molecular-weight heparin for the patients at high risk. The results of published reports of protection against pulmonary embolism and deep venous thrombosis with multimodal treatment are as good as or better than the results of published reports of protection with warfarin or low-molecular-weight heparin, with a lower rate of bleeding complications9-14.
unfortunately, in the current study, Eisele et al. have not reported the data that are needed by the orthopaedic community to substantiate the efficacy of the treatments used. The reader is left to assume there is no occurrence of pulmonary embolism because these data are never stated in the article. The reader must wonder whether the authors measured only deep venous thrombosis. The second deficiency is the absence of any data on clinical outcomes other than deep venous thrombosis. The failure to report clinical outcomes is a major limitation, and a disturbing precedent, of thromboembolic studies conducted by drug companies investigating warfarin or low-molecular-weight heparin9-14. A comprehensive evaluation of the efficacy of a prophylactic treatment against thromboembolism necessitates data on overall deaths (particularly deaths from bleeding complications), wound hematomas (and reoperations required), and wound drainage and infection. It is the occurrence of these clinical outcomes that has stimulated some in the orthopaedic community to seek alternative treatments to chemical anticoagulation15. Since this study used low-molecular-weight heparin (certoparin), and low-molecular-weight heparin (enoxaparin) has been shown to cause the most bleeding complications10,11, we cannot recommend the use of low-molecular-weight heparin with intermittent pneumatic compression treatment, despite the superb protection against deep venous thrombosis (and possibly pulmonary embolism) that this treatment affords, until the data on clinical outcomes are provided for our review. We would also suggest that orthopaedic journals make an editorial policy that these data be included in all published articles on prophylactic treatment against thromboembolism.
*The authors did not receive any outside funding or grants in support of their research for or preparation of this work. Neither they nor a member of their immediate families received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, division, center, clinical practice, or other charitable or nonprofit organization with which the authors, or a member of their immediate families, are affiliated or associated.
1. Lachiewicz PF, Soileau ES. Multimodal prophylaxis for THA with mechanical compression. Clin Orthop Relat Res. 2006;453:225-30.
2. Lotke PA, Lonner JH. The benefit of aspirin chemoprophylaxis for thromboembolism after total knee arthroplasty. Clin Orthop Relat Res. 2006;452:175-80.
3. Geerts WH, Pineo GF, Heit JA, Bergqvist D, Lassen MR, Colwell CW, Ray JG. Prevention of venous thromboembolism: the seventh ACCP conference on antithrombotic and thrombolytic therapy. Chest. 2004;126(3 Suppl):338S-400S.
4. Hooker JA, Lachiewicz PF, Kelley SS. Efficacy of prophylaxis against thromboembolism with intermittent pneumatic compression after primary and revision total hip arthroplasty. J Bone Joint Surg Am. 1999;81:690-6.
5. Gonzalez Della Valle A, Serota A, Go G, Sorriaux G, Sculco TP, Sharrock NE, Salvati EA. Venous thromboembolism is rare with a multimodal prophylaxis protocol after total hip arthroplasty. Clin Orthop Relat Res. 2006;444:146-53.
6. Salvati EA, Pellegrini VD Jr, Sharrock NE, Lotke PA, Murray DW, Potter H, Westrich GH. Recent advances in venous thromboembolic prophylaxis during and after total hip replacement. J Bone Joint Surg Am. 2000;82:252-70.
7. Sculco TP, Colwell CW Jr, Pellegrini VD Jr, Westrich GH, Böttner F. Prophylaxis against venous thromboembolic disease in patients having a total hip or knee arthroplasty. J Bone Joint Surg Am. 2002;84:466-77.
8. Larson CM, MacMillan DP, Lachiewicz PF. Thromboembolism after total knee arthroplasty: intermittent pneumatic compression and aspirin prophylaxis. J South Orthop Assoc. 2001;10:155-63.
9. Colwell CW Jr, Berkowitz SD, Lieberman JR, Comp PC, Ginsberg JS, Paiement G, McElhattan J, Roth AW, Francis CW; EXULT B Study Group. Oral direct thrombin inhibitor ximelagatran compared with warfarin for the prevention of venous thromboembolism after total knee arthroplasty. J Bone Joint Surg Am. 2005;87:2169-77.
10. Colwell CW Jr, Collis DK, Paulson R, McCutchen JW, Bigler GT, Lutz S, Hardwick ME. Comparison of enoxaparin and warfarin for the prevention of venous thromboembolic disease after total hip arthroplasty. Evaluation during hospitalization and three months after discharge. J Bone Joint Surg Am. 1999;81:932-40.
11. Fitzgerald RH Jr, Spiro TE, Trowbridge AA, Gardiner GA Jr, Whitsett TL, O'Connell MB, Ohar JA, Young TR; Enoxaparin Clinical Trial Group. Prevention of venous thromboembolic disease following primary total knee arthroplasty. A randomized, multicenter, open-label, parallel-group comparison of enoxaparin and warfarin. J Bone Joint Surg Am. 2001;83:900-6.
12. Francis CW, Pellegrini VD Jr, Totterman S, Boyd AD Jr, Marder VJ, Liebert KM, Stulberg BN, Ayers DC, Rosenberg A, Kessler C, Johanson NA. Prevention of deep-vein thrombosis after total hip arthroplasty. Comparison of warfarin and dalteparin. J Bone Joint Surg Am. 1997;79:1365-72.
13. Lieberman JR, Wollaeger J, Dorey F, Thomas BJ, Kilgus DJ, Grecula MJ, Finerman GA, Amstutz HC. The efficacy of prophylaxis with low-dose warfarin for prevention of pulmonary embolism following total hip arthroplasty. J Bone Joint Surg Am. 1997;79:319-25.
14. Pellegrini VD Jr, Clement D, Lush-Ehmann C, Keller GS, Evarts CM. Natural history of thromboembolic disease after total hip arthroplasty. Clin Orthop Relat Res. 1996:333;27-40.
15. Callaghan JJ, Dorr LD, Engh GA, Hanssen AD, Healy WL, Lachiewicz PF, Lonner JH, Lotke PA, Ranawat CS, Ritter MA, Salvati EA, Sculco TP, Thornhill TS; American College of Chest Physicians. Prophylaxis for thromboembolic disease: recommendations from the American College of Chest Physicians--are they appropriate for orthopaedic surgery? J Arthroplasty. 2005;20:273-4.