General Observations A Podiatrist can tell a lot about your circulation just by looking at your feet. What colour is the skin? How dry is it? What's going on with those nails? These baseline checks can help to give a general overview as to your foot health. Palpate Pedal Pulses Good practice is to check the pedal pulses by applying as many fingers as possible (typically 4) to the corresponding areas of the feet; the dorsalis pedis (top of the foot, usually felt somewhere along the 2nd metatarsal) and posterior tibial (inside of the foot, typically behind the ankle bone).
Check Capillary Refill Time Another quick test is to push down the skin on the top of the big toe with your thumb for 5 seconds (until the skin blanches/goes white), release the thumb, and count how long it takes for the colour of the skin to return to 'normal'. This is a Capillary Refill Time (CRT) and helps to gauge what the smallest blood vessels are up to. A normal CRT in the foot is 3 seconds or less, which indicates normal blood volume and perfusion. However, it's important to note that dehydration, outside temperature & footwear choice (i.e. wearing flip flops on a cold day) can affect your 'normal'. A CRT of more than 3 seconds could indicate a problem with the circulation. Doppler Ultrasound A Doppler ultrasound test uses reflected sound waves to evaluate blood as it flows through a blood vessel. It helps evaluate blood flow through the major arteries of the feet and is used to assess the quality of the circulation to the feet. Interesting Fact: Atrial Fibrillation can be picked up by using Doppler ultrasound on the feet.
During Doppler ultrasound, ultrasound gel is applied to the appropriate area of the foot and the doppler probe (transducer) is moved gently over the skin above an artery (blood vessel that carries blood away from the heart). The transducer sends and receives high frequency sound waves that are amplified through a microphone. The podiatrist listens to the sounds produced to evaluate the blood flow through the vessel. There's a short video on YouTube demonstrating this here. This assessment is commonly performed during diabetes checks and neurovascular assessments (typically performed during an initial appointment at Oxfordshire Chiropody & Podiatry). Based on what the podiatrist hears, they can determine how much blood is going through an artery and whether there is a problem with the peripheral circulation.
Arteries are elastic and will stretch and relax to allow the blood to flow through the vessel and reach its destination. Ideally 2 or 3’s noises should be heard as per the beat of the heart, as the blood recoils in the artery.
What can poor circulation lead to? A good blood circulation is necessary for muscle, skin, bone and nerve health. Poor circulation to the toes can cause chilblains and peripheral neuropathy. More seriously, a reduced blood supply can contribute to ulcers and gangrene (necrosis). An ulcer can be caused when a person with a reduced blood supply injures themselves and then healing is delayed second to their poor blood supply.
A person with a foot deformity, such as a bunion, may be advised not to pursue surgery to correct the deformity as the foot may not have an adequate blood supply to fully heal after the procedure.
Questions? Get in touch!