Case 2

A 32 year old female presents to the emergency department with a 4 day history of swelling and pain of the right lower limb. She denies any recent trauma to the area however tells us that she has recently had a plaster removed after surgery for a broken ankle. Over the past 4 days the calf has gotten increasingly erythematous, swollen and is associated with crampy calf pain when walking.

On examination the patient’s right calf is swollen (measuring 35cm in comparison to 31cm on the left) with pitting oedema to the level of the mid-calf. The leg is erythematous. Cap refill is less than 2 seconds with strong pulses.

There is no obvious breakages to the skin or infected toenails.

The patient has full range of movement of the ankle and knee. Her observations are;

HR 86 and regular, RR 14, SpO2 98% on RA, BP 120/82, Afebrile

Question 1.

What is the most likely diagnosis in this patient?

Question 2.

What differential diagnoses must be considered?

Question 3.

What clinical decision tool is used to determine the probability of this diagnosis?