35 Year Old Woman Complaining Of Pain In Her Right Calf

A 35 year old female presents to the hospital with the complains of pain in her right calf that started a few days ago and is now worsening. The pain is constant , 8/10 in intensity, and aggravated on walking and extending the knee. It is associated with swelling and redness of her calf region. The pain is slightly relieved by elevation of her foot and on taking ibuprofen. Patient gives a history of travelling a 15 hour flight 1 week ago. She is on oral contraceptive pills for last 2 years.
On examination the right calf appears red and swollen compared to the left side but there is no ulceration or abnormal pigmentation. On palpation the right calf is warmer compared to the left and there is a positive pitting pedal edema on the right side. The pulses are palpable and felt equal on both sides. Mobility is normal on both sides in the ankle, knee and hip joints. There is a positive Homan's sign on the right side.
The picture of her legs is shown below:

What is the differential diagnosis?

• Deep vein thrombosis
• Cellulitis
• Myositis
• Rupture of Baker's cyst
• Hematoma
• Spasm due to injury or sprain

What workup is advised in the above described case?

• Doppler Ultrasound
• D-dimer
• Hypercoagulability testing
• CBC with differential
• CPK and myoglobin level
• CT venography

Case Discussion:

1. Deep vein thrombosis: DVT is common in lower limbs and may arise under conditions of stasis, hypercoagulability and venous endothelial injury. Conditions that result in prolonged immobilization such as post surgery, trauma, sedentary jobs or long hours of travel are the predisposing factors. DVT may produce pain and edema of affected limb or may be asymptomatic. A positive Homan's sign ( pain on dorsiflexion of the ankle) is indicative of DVT. 

2. Cellulitis or Myositis: Trauma can lead to cellulitis of the skin and subcutaneous tissue or myositis of the calf muscle. All classical signs of inflammation that is pain, redness, swelling as well as fever are present.

3. Hematoma: Injuries can cause bleeding intramuscularly and the patients may present with pain, swelling and restricted movements.

4. Spasm/ Strain: Undue strain may cause physical tearing of muscles or tendons inducing spasms and pain.

5. Doppler Ultrasound: is an initial diagnostic test that is non invasive and can help visualize clots in the veins of the legs.