CanadiEM Frontline Primer

CanadiEM Frontline Primer – Lower Leg Swelling

In Medical Concepts by Ryan O'ReillyLeave a Comment

Can’t Miss Diagnoses



  • DVT (proximal, isolated distal)
  • Arterial Occlusion
  • Cellulitis
  • MSK
  • Septic Joint
  • Bursitis
  • Fracture
  • Ruptured Baker’s Cyst
  • Compartment Syndrome
  • Superficial Thrombophlebitis
  • Necrotizing Fasciitis
  • HematomaMyositis


  • Bilateral DVT
  • Cellulitis
  • CHF Exacerbation
  • Constrictive Pericarditis
  • AKI
  • Nephrotic Syndrome
  • IVC Thrombosis
  • Medication Adverse Event
  • Preeclampsia

Considerations in the age of COVID-19 for your safety: Many individuals with COVID-19 can present entirely asymptomatically, without cough or fever. If the rate of COVID-19 is high in your community, consider taking appropriate precautions even for this presentation. Also, consider that COVID-19 related sepsis may be a pro-thrombotic state. Early studies may show that there is an elevated D-Dimer with those with COVID-19.

Common Chronic Manifestations

Chronic – Venous Insufficiency, Peripheral Arterial Disease, Secondary Lymphedema (tumour, radiation, surgery), Venous malformation, Reflex Sympathetic Dystrophy

Chronic – CHF, CKD, Venous Insufficiency, Peripheral Arterial Disease, Lymphedema, Liver Failure/Cirrhosis, Pulmonary HTN, Pregnancy, Hypothyroidism, Lipedema, Reflex Sympathetic Dystrophy, Hypoalbunemia, Malnutrition, Medication Adverse Effect

Points to focus upon

Lower extremity swelling and pain are common presentations to the ED, although many presentations are linked to an exacerbation of a systemic illness. Once a history of acute trauma has been excluded, it is important to distinguish between etiologies for unilateral and bilateral presentations. Among patients with unilateral leg swelling/pain who were worked-up for DVT, the prevalence of a confirmed DVT was 19% on average.(1)


Chronicity of the disease process.
History of venous thromboembolism, kidney/liver/heart failure
History of recent injury, immobilization, surgery/procedures.
Associated symptoms (breathlessness, chest pain, hemoptysis, PNDs/Orthopnea)
Medication History, Recent Surgical/Trauma History


Location of leg swelling
Associated redness near or at the swelling
Pattern of pitting edema (Does it follow a deep vein?)


  • Ultrasound & D-Dimer (DVT)
  • CXR & EKG (CHF)
  • Ankle-Brachial Index (Venous Insufficiency)
  • CBC (Anemia)
  • Liver Enzymes (Cirrhosis, HELLP), Albumin (Nephrotic syndrome, hypoalbuminemia)
  • Creatinine (AKI, CKD)
  • Urinalysis (protein = nephrotic syndrome)
  • Urine β-hCG (Pregnancy, Preeclampsia)
  • TSH +/- T3/4 (Hypothyroidism)
  • Compartment Pressure (Compartment Syndrome)

Clinical Decision Rules

CanadiEM Frontline Primer - Lower Leg Swelling
Algorithm for DVT Testing


We will cover two of the more common acute leg swelling pathologies (DVT and thrombophlebitis). If there is a more systemic cause, the key will be to begin treatment of the underlying condition (e.g. diuresis for CHF).

DVT Management
For stable outpatients starting anticoagulant therapy:
Warfarin (bridged with 5-7 days of Low Molecular Weight Heparin subcutaneous injections)
Direct Oral Anticoagulant (Dabigatran, Rivaroxaban, or Apixaban)
Pregnant patients will require other forms of treatment such as low molecular weight heparin injections.
Read more here.

NSAIDs +/- compression stockings

Recommended reading, videos, and podcasts

The following is part of the CanadiEM Frontline Primer. An introduction to the primer can be found here. To return to the Primer content overview click here.

This post was edited by Dr. Brent Thoma MD FRCPC. This post was copyedited and uploaded by Evan Formosa.

Ryan O'Reilly

Ryan O'Reilly is a Family Medicine Resident at McMaster University. His interests include medical education, PoCUS, decision analysis, and following the every move of his favourite team, Liverpool FC.

Teresa Chan

Senior Editor at CanadiEM
Emergency Physician. Medical Educator. #FOAMed Supporter, Producer and Researcher. Chief Strategy Officer of CanadiEM. Associate Professor, Division of Emergency Medicine, Department of Medicine, McMaster University.