ReviewDoes thromboprophylaxis reduce symptomatic venous thromboembolism in patients with below knee cast treatment for foot and ankle trauma? A systematic review and meta-analysis
Introduction
Patients with foot and ankle trauma treated with cast or splint immobilization are at risk of venous thromboembolism (VTE) [1]. The most serious complication of this is death from Pulmonary Embolism (PE), which occurs in approximately 1 in 15,000 patients [2]. Although fatal pulmonary embolism is the most serious thromboembolic complication, it is not the only significant adverse event. Approximately 1 in 500 patients will develop a symptomatic PE within 90 days of injury [2]. Many of these patients will be functionally impaired at long term follow up [3]. The other significant complication is symptomatic deep venous thrombosis, which occurs in approximately 1 in 250 patients with non-operatively treated foot and ankle trauma [4]. 20–50% of these patients will develop post thrombotic syndrome [5]. This condition is difficult to treat and therefore it is important to avoid. Considering that lower limb casts and splints are commonly used for a variety of soft tissue and bony traumatic conditions, the population of patients at risk of developing VTE is significant. In view of this, NICE guidelines recommend that patients with foot and ankle trauma and lower limb immobilization should be assessed for risk of development of VTE, and provided with chemical thromboprophylaxis if they have additional risk factors (including cancer, thrombophilia, previous venous thrombosis) [1]. Prophylactic options include either chemical or mechanical methods.
Our aim was to determine the current evidence for the use of chemical or mechanical thromboprophylaxis in the prevention of symptomatic venous thromboembolism in adult patients with foot or ankle trauma treated with below knee cast or splint immobilization. Our secondary aim was to report episodes of major bleeding associated with thromboprophylaxis.
Section snippets
Methods
The OVID interface was used to search MEDLINE and EMBASE databases up to 1st June 2015. The following search strategy, previously used by Roberts et al. (2012) was used [6]: (exp venous thrombosis OR exp thromboembolism OR exp pulmonary embolism OR DVT.mp OR deep vein thrombosis.mp OR PE.mp OR pulmonary embolism.mp OR venous thromb$.mp) AND (exp casts surgical OR plaster cast$.mp OR exp immobilization OR immobilization.mp). The search was limited to randomized controlled trials, with no
Results
Seven prospective randomized controlled trials were included in this review (Table 1). Study details are displayed in Table 2. All of these studies focused on chemical thromboprophylaxis. Only two studies considered patients treated non-operatively [7], [8], with all others including patients who underwent surgery. One focused on patients with ankle fractures [9], one focused on Achilles tendon ruptures [10], and the remaining 5 studies include patients with a variety of soft tissue and bony
Discussion
Orthopaedic surgical patients are generally regarded as high risk of venous thromboembolic complications. Patients undergoing surgery for hip fracture, total hip or knee replacement have deep vein thrombosis incidences of up to 60% [1]. Prevention of VTE is more desirable than treating VTE events from both a clinical and financial perspective [19], and there is no doubt that mechanical and chemical thrombo prophylaxis are effective in patients undergoing major Orthopaedic surgery. For example,
Conflicts of interest statement
None declared.
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