Please select the eligibility criteria that correspond to the clinical trial below.
Title: Clinically-Important Venous Thromboembolism Following Lower Extremity Fractures: Epidemiology & Prevention
Brief Summary: It is known that patients who fracture their legs sometimes develop blood clots (known as deep vein thrombosis) in their legs. These clots may cause pain and swelling in the leg or they may detach and travel to the lungs producing shortness of breath, chest pain, and sometimes death. Unfortunately, it is not known how frequently these complications occur after leg fractures, or if the use of a blood thinner medication can effectively and safely prevent these clots. Doctors at hospitals across Canada are conducting a study in which patients who have surgery for leg fractures receive either a once-daily injection of a blood thinner, known as low molecular weight heparin, or a placebo injection for up to 14 days after their fractures. Neither the patients nor the doctors know which patient is on the medication and which patient is on placebo. All patients receive an ultrasound examination of their legs at 2 weeks after surgery to monitor for deep vein thrombosis. In addition, all patients are checked for symptoms of leg or lung clots and any side effects of the medication for 3 months. If the blood thinner is shown to be effective at reducing this complication and documented to be safe and cost-effective in this setting it will be recommended for use in such patients. If, on the other hand, the frequency of deep vein thrombosis is too low to justify the cost or inconvenience of taking this medication, this will also be an important finding.


Options:
A: Inclusion Criteria:

* Age \> 16 years
* Unilateral or bilateral, closed or open, fractures of the lower extremity distal to the knee including:

  1. Isolated fractures of the tibia including tibial plateau, shaft and plafond and medial malleolus
  2. Isolated fractures of the fibula including fibular head, fibular diaphysis,distal fibula and lateral malleolus
  3. Combined fractures of the tibia and fibula
* Tibia and/or fibula fractures may be accompanied by fractures of the patella and/or foot as well as ligamentous injuries as long as either the tibia or the fibula is involved
* Patients must be scheduled to undergo surgery (internal or external fixation) for repair of their fracture during the current admission

Exclusion Criteria:

* Patients presenting greater than 72 hours after injury
* Major injury involving other site(s)
* Lower extremity vascular injury requiring surgical repair
* Known systemic bleeding disorder or INR \> 1.5, aPTT \> 40 sec, or platelets \< 50 x 109/L at baseline
* Active, uncontrolled bleeding (as determined by the attending surgeon or delegate)
* Intracranial or other major bleed in the previous 4 weeks
* Ongoing need for anticoagulation for other reasons
* Previous DVT or PE (objectively proven or treated with anticoagulants)
* Known molecular hypercoagulable state
* Active cancer
* Inability to receive contrast dye because of pregnancy, contrast allergy, or renal failure (serum creatinine \> 300 mmol/L)
* Hypersensitivity to heparin or LMWH (including history of HIT)
* Inability to arrange out-of-hospital study medication administration
* Anticipated inability to undergo endpoint duplex ultrasound or follow-up (day 14 ± 2, 6 weeks, 3 months)
* Inability or refusal to provide informed consent· Previous participation in this study
* Estimated weight less than 40 kg
B: Inclusion Criteria:

* Meniscectomy
* Diagnostic Arthroscopy
* Removal of corpora libera

Exclusion Criteria:

* Contra-indications for LMWH use (recent major bleeding, bleeding disorder, allergy)
* Pregnancy
* Pre-existent indication for anticoagulation therapy, either LMWH or vitamin K antagonists.
* History of venous thromboembolism (indication for anticoagulation therapy for prophylaxis of recurrence)
* Mental of physical disability to fulfill study requirements
* Insufficient knowledge of the Dutch language
* Previous participation in the Pot-(K)Cast study
C: Inclusion Criteria:

All patients in need of immobilization of the lower leg with a plaster cast (or equivalent of a cast) for a minimum of one week for the following indications:

* Trauma of the lower leg
* Surgery of the lower leg followed by lower leg immobilization with a plaster cast
* Non-traumatic indications

Exclusion Criteria:

* Contra-indications for LMWH use (recent major bleeding, bleeding disorder, allergy)
* Pregnancy
* Pre-existent indication for anticoagulation therapy, either LMWH or vitamin K antagonists.
* History of venous thromboembolism (indication for anticoagulation therapy for prophylaxis of recurrence)
* Mental of physical disability to fulfill study requirements
* Insufficient knowledge of the Dutch language
* Previous participation in the Pot-(K)Cast study
D: Inclusion Criteria:

1. Patient is \>/= 18 years of age
2. Actual body weight is \>/= 45 kg
3. Admission to ICU expected to be \>/= 72 hours in duration

Exclusion Criteria:

1. Neurosurgery within last 3 months
2. Ischemic stroke within last 3 months
3. Intracranial hemorrhage within last 3 months
4. Systolic Blood Pressure \>/= 180mm Hg, Diastolic Blood Pressure \>/= 110mm Hg for \>/= 12 hours requiring vasoactive drug infusion
5. Major hemorrhage within last week unless definitively treated
6. Coagulopathy as defined by INR \>/= 2 times upper limit of normal \[ULN\], or PTT \>/= 2 times ULN, at time of screening
7. Thrombocytopenia defined as platelet count \</= 75 x 109/L, at time of screening
8. Other heparin contraindications (e.g., HIT, pregnancy, lactating)
9. Contraindication to blood products (e.g., Jehovah's Witness)
10. Unable to perform lower limb ultrasound (e.g., bilateral above the knee amputation, or severe distal extremity burns)
11. Limitation of life support, Life expectancy \</= 14 days, or palliative care
12. Contamination (e.g., \>/= 3 doses of LMWH during this ICU admission)
13. Lack of informed consent

Answer: A