Prolonged thromboprophylaxis with Dalteparin during immobilization after ankle fracture surgery: A randomized placebo-controlled, double-blind study

Abstract

BackgroundSkeletal trauma and immobilization are well-known risk factors for deep vein thrombosis (DVT) and pulmonary embolism (PE). While prophylaxis against thromboembolic complications has become routine after major orthopedic surgery, whether or not prophylaxis after minor surgery and lower limb immobilization is necessary is still under debate.Methods In a double-blind, placebo-controlled study, 272 consecutive patients were randomized to receive either thromboprophylaxis with Dalteparin (n = 136) or placebo (n = 136) for 5 weeks after ankle fracture surgery. All patients received 1 week of initial treatment with Dalteparin before randomization. A unilateral phlebography was performed when the cast was removed.Results The overall incidence of DVT was 21% (95% CI: 13-29%) in the Dalteparin group and 28% (CI: 19-37%) in the placebo group (risk ratio = 0.8, CI: 0.6-1.1; p = 0.3). The incidence of proximal DVTs was 4% and 3%, respectively. No major bleeding occurred.Interpretation We found no significant difference in the incidence of DVT between the 2 treatment groups and our results do not support prolonged thromboprophylaxis. The overall incidence of DVT was high, reflecting the potential risk of PE and post-thrombotic syndrome after ankle fracture surgery. Most of the DVTs were asymptomatic, however, and were located in distal veins.

Intermittent pneumatic compression reduces the risk of deep vein thrombosis during post-operative lower limb immobilisation

“…The frequency of DVT in the control group (37%) found in this study is in agreement with previously reported, 36%, in other randomized controlled studies on CDU verified DVT after surgical treatment of acute ATR (6)(7)(8). The characteristics of the patient population in this study did not differ from that of the three earlier studies reporting on DVT rates after ATR surgery (7,8,16).…”

“…Earlier investigations demonstrated no DVTpreventive effect with LMWH in ATR patients. (6) This study, however, established IPC prophylaxis as a feasible and efficient treatment alternative, at least during early immobilisation.…”

“…Patients immobilised in plaster cast after Achilles tendon rupture (ATR) are at especially high risk; the VTE incidence being 36-50%, irrespective of operation or conservative treatment (6)(7)(8). Hence, DVT preventive interventions during lower limb immobilisation are, although debatable (9), often recommended (5).…”

The benefit of pharmacological venous thromboprophylaxis in foot and ankle surgery

“…[35] Lapidus et al, [36] however, found a 28% DVT rate in patients after ankle fracture surgery who did not receive pharmacological prophylaxis. In two studies following Achilles tendon rupture repair, the incidences of DVT were 36% [19] and 6%.…”

Effects of Long-Term Low-Molecular-Weight Heparin on Fractures and Bone Density in Non-Pregnant Adults: A Systematic Review With Meta-Analysis

“…[12][13][14] Studies assessing the safety of long-term LMWH against oral vitamin K antagonists (VKAs) or novel anticoagulants in cancer or other populations were designed to address more common side effects: the risk of bleeding and thrombocytopenia. [15][16][17][18][19][20][21][22][23][24][25][26][27][28] The adverse effects of long-term LMWH on bone in terms of increased risks of fractures (i.e., clinically most important but rare outcomes) and bone loss are less commonly researched and unclear. The effects of LMWH on bone were mainly studied in the pregnant population.…”