Summary Deep vein thrombosis (DVT) is a common complication that is caused by a blood clot originating in deep veins and propagating proximally. This condition most commonly presents in middle-aged and elderly adults with swelling and pain in the calf. Diagnosis is made in combination with a clinical examination that demonstrates calf pain and swelling, as well as advanced imaging (e.g., duplex ultrasound). Treatment of DVT is primarily anticoagulation to prevent further morbidity, and in some instances, thrombolytic therapy and/or surgical intervention is indicated. Introduction Introduction procedures associated with a greater risk of DVT spine fracture with paralysis elective total knee arthroplasty login to view 1 more bullet elective total hip arthroplasty login to view 1 more bullet hip fracture polytrauma based on AAOS review, the rate of DVT does not correlate with PE or death following THA or TKA Epidemiology Incidence 80 cases per 100,000 per year 1 lower extremity case per 1,000 each year 2.5-5% of the population is affected Demographics rare in children typically >40 years of age unknown sex bias African American and White populations are at increased risk Location upper extremity lower extremity proximal location login to view 1 more bullet distal location login to view 3 more bullets Risk factors immobilization mechanical compression trauma history of DVT surgery polycythemia vera thrombocytosis dehydration Etiology Pathophysiology mechanism virchow's triad login to view 3 more bullets pathoanatomy thrombin interaction with the endothelium stimulates cytokine production and leukocyte adhesion thrombus propagation is dependent on the balance between coagulation and thrombolytic pathways Associated conditions medical malignancy congestive heart failure destructive airway disease orthopedic patients undergoing surgery Anatomy Upper extremity deep veins radial ulnar brachial axillary subclavian internal jugular brachiocephalic Lower extremity proximal popliteal vein and proximal distal axial login to view 3 more bullets muscular login to view 2 more bullets Presentation History previous surgery state of hypercoagulability recent immobilization recent injury Symptoms common extremity swelling (70%) calf pain (50%) redness warmth Physical exam often more helpful than imaging lower extremity swelling (unilateral or bilateral) erythema and warmth of skin dilated veins tenderness with palpation Homan's sign is not very specific Imaging Contrast venography historical gold standard venous contrast with fluoroscopy invasive procedure with direct visualization of venous clot can be used when ultrasound is unavailable or inconclusive Ultrasonography complete duplex ultrasound first-line imaging modality login to view 1 more bullet 96% sensitive, 97% specific; operator dependent login to view 1 more bullet findings login to view 3 more bullets Advanced imaging Magnetic resonance direct thrombus imaging (MRDTI) MRI with contrast dye to visualize venous thrombus 90% sensitive, 90% specific not widely used alternative to duplex ultrasound CT venography CT scan with contrast dye to visualize venous thrombus 90% sensitive, 95% specific useful when pulmonary embolism is suspected or following an inconclusive ultrasound study Additional information for proximal DVTs (proximal to trifurcation) complete duplex ultrasound (96% sensitive, 97% specific) plethysmography (75% sensitive, 90% specific) CT (90% sensitive, 95% specific) Studies D-Dimer testing high sensitivity (low specificity) for VTE excludes VTE without the need for further testing among patients with a low clinical probability of PE not helpful post-injury or surgery levels > 500 ng/mL suggest the presence of PE Differential Cellulitis infectious laboratory findings Post-thrombotic syndrome history of DVT, chronic swelling, and venous stasis ulcers Ruptured Baker cyst ultrasound findings without a venous thrombus Trauma radiographs demonstrating an underlying fracture that is causing edema and pain Superficial thrombophlebitis cord-like superficial vein on exam with superficial venous thrombus on ultrasound Congestive heart failure notable medical history with chronic bilateral lower extremity peripheral edema Nephrotic syndrome notable medical history with chronic bilateral lower extremity peripheral edema Liver cirrhosis notable medical history with chronic bilateral lower extremity peripheral edema Treatment Nonoperative Oral anticoagulation therapy indications login to view 2 more bullets oral anticoagulation medications login to view 10 more bullets duration login to view 16 more bullets thrombolytic therapy considered in those with life or limb-threatening PE or acute DVT associated with high risk of morbidity Operative vena cava filter placement indications login to view 2 more bullets thrombectomy indications login to view 2 more bullets catheter-directed thrombolysis indications login to view 1 more bullet Complications Postthrombotic syndrome: chronic venous insufficiency venous HTN chronic skin issues (swelling, pain, pigmentation, ulceration, induration) recurrent DVT (4-8x higher after first DVT) Pulmonary emboli 1 in 1,000 cases annually diagnosis via advanced imaging and clinical exam treatment with oral/IV therapeutic anticoagulation with/without surgical intervention Excessive bleeding from anticoagulation medication from thrombolytic therapy