Introduction
Located at the back of the leg, the posterior tibial veins are involved in certain conditions such as deep vein thrombosis (DVT) and chronic venous insufficiency. This article will focus on one particular vein in the body- the posterior tibial vein, and its clinical significance.
Veins vs arteries
The circulatory system (in simplified terms) includes arteries which take oxygenated blood away from the heart and to the organs, and veins, which take deoxygenated blood away from the organs and back to the heart.
Arteries have a thicker layer of muscle to be able to move blood away at some force. Veins have thinner walls compared to arteries and have lower blood pressure. Because of the thinner muscle walls, there is a lower pressure of blood in veins compared to arteries. Veins also have valves in them (valves are not present in arteries), as shown in the diagram below, which ensure that blood flows in one direction.
The veins carry deoxygenated blood- drained from the different organs of the body- to the heart. From the heart, the blood then goes to the lungs where it is oxygenated again before it goes back around to the rest of the body. This is relevant for the clinical significance of the posterior tibial vein.1
Where is the posterior tibial vein?
The diagram above (adapted from the source) shows the veins of the lower limb (starting from the knee down). ‘Anterior’ means in front, meaning the person is facing towards you, and ‘posterior’ means behind, so the posterior view shows if they are facing away.
The bigger of the two bones in the calf is the tibia (this is the shin bone), and the smaller one is the fibula. The posterior tibial vein is therefore the vein that runs behind the tibia. There are two posterior tibial veins in the body- one on the right and one on the left. In the article however, I will be referring to it in the singular form and plural form interchangeably.
The posterior tibial vein drains blood from (in part), the foot, ankle and the back of the leg.1
Deep vein thrombosis (DVT)
DVT is a condition where the blood in the veins forms a clot, known as a thrombus. This usually occurs in the legs. It can halt blood flow completely or partially. It is known as a ‘deep vein’ as these are the veins deep inside the body, as opposed to superficial veins which are closer to the surface of the skin.
If this blood clot breaks off and travels in the bloodstream, the travelling blood clot is known as an embolus. When the blood eventually goes back to the heart and then the lungs, the blood clot can lodge itself into one of the smaller blood vessels within the lungs- known as pulmonary embolism (PE). These can be life-threatening.3
When reading about this topic, you may also come across the term venous thromboembolism (VTE) which is a collective term for disorders caused by blood clots in the veins.
DVT usually occurs in the veins of the leg- it can occur in the veins further up the leg in like the thigh. However, it can also occur in the veins of the calf as well- around 20% of DVTs occur in one of the veins in the calf, of which the posterior tibial vein is one.
Adapted from BioRender by Ana Kuznetsova
Classification
DVT can be classified according to where in the leg the clot comes from:
- ‘Proximal’ DVTs occur above the knee- in the veins of the thigh, usually the femoral or common femoral vein
- ‘Distal’ DVTs occur below the knee- in the veins of the calf. A DVT in the posterior tibial vein would be classed under distal DVT
It is worth noting that proximal DVTs are much more likely to lead to PEs or other complications (as compared to distal DVTs), and can in many cases be fatal. After heart attacks and strokes, they are the third most common cause of death from cardiovascular disease. Most cases of PE are caused by DVT in the legs.
Although the mortality from a DVT in the posterior tibial vein is relatively low, it does increase the risk of a recurrent DVT (meaning having it again). This can be a significant cause of morbidity.4
Symptoms
The most common symptom of DVT is pain and swelling in the calf, although hospital tests will need to be taken to diagnose a DVT, as it cannot be differentiated from other conditions that cause pain in the calf from symptoms alone.
- Proximal DVTs are more commonly associated with “classical” symptoms of DVTs of pain, swelling and heaviness of the calf. This is because the flood flow from most of the limb below the knee is blocked further up the leg, so the blood is unable to flow out of this area. Proximal DVT makes up 80% of all DVT cases2
- Distal DVTs usually do not have this kind of swelling as the area that is blocked is much smaller4
Treatment of DVT
- Treatment of DVTs is usually described for proximal DVTs- intravenous anticoagulation therapy at the time and lifelong oral anticoagulants afterwards4
Distal DVT treatment, to quote one paper “remains uncertain”. However, if left untreated, it has been established that distal venous thromboembolism can move to the veins in the thigh, where it can become a proximal VTE. It is therefore important for it to be treated
Complications
One other uncommon complication of a DVT in the posterior vein is that the thrombus (blood clot within the vein) can cause a physical obstruction to the surrounding anatomy. There has been evidence that tarsal tunnel syndrome (compression of one of the nerves that go to the foot) has been caused by a DVT in the calf. Symptoms are usually of pain and altered sensation in the foot.6
Causes and risk factors for DVT
Obesity is one of the main causes of VTE (and cardiovascular disease). In obese people, the most common cause of death is PE from DVT.
- Damage to the veins can also increase the risk of DVTs:
- This can be from a surgery, previously inserted catheters in the veins or from previous DVTs
- Intravenous drug abuse also injures veins and can give rise to DVTs
- Other reasons include physical obstructions like a tumour that is blocking the veins, in pregnancy there can be reduced blood flow as well
- Certain blood disorders can also make the blood more prone to clotting, and increase risk of DVT.
- Immobility- this may be from prolonged periods of bed rest, for example after hospitalisation, or from a long flight journey
- Other factors that increase risk include:
- High blood pressure
- Diabetes
- Smoking
- Cancer
- Inflammatory bowel disease
- A very small risk with oral contraceptives containing oestrogen
Chronic venous insufficiency (CVI)
CVI is a long-term condition where the veins are damaged and their ability to return blood back to the heart is affected. This can be seen in the image on the left (source).
CVI can arise from a DVT, which causes damage to the affected vein. This can include the posterior tibial vein.6
Many cases of CVI are asymptomatic, but common symptoms of CVI include:
- Pain and swelling in the lower legs
- Pain and swelling can range from mild to severe
- There may be a feeling of heaviness and discomfort, especially after periods of sitting or standing
- In some severe cases, the veins can ulcerate and cause infections
There can also be skin changes in the affected leg, such as:
- Development of varicose veins (bulging veins under the skin),
- Telangiectasia (or spider veins)
- Reticular veins
- Discolouration
- Thickening of the skin
The skin changes can often be without any pain or discomfort, but the cosmetic change is often a cause of concern for many patients.6
Risk factors
Risk factors for CVI are similar to the risk factors for DVTs. These include:
- Obesity
- High blood pressure
- Smoking
- Increased age (over 60 years)
- High oestrogen levels (from contraception for example)
Treatment
Treatment of CVI is dependent on the case:
- Compression stockings (usually up to the knee) are often used and work well
- Sometimes medications which act on the veins can be given. Flavonoids are a common group of medications, although these have had varying levels of success and can come with side effects. In more severe cases, veins can be operated on surgically to improve the cosmetic appearance and reduce the risk of ulceration. Common methods of surgery are ligation of the veins or ablation5
- Lifestyle modification - maintaining a healthy weight, stopping smoking and avoiding a sedentary lifestyle - is also a part of reducing risk
Summary
The posterior tibial vein is one of the veins in the calf, running behind the tibia bone. It drains blood from part of the foot and ankle. This vein does have significance clinically. Deep vein thrombosis can occur in the posterior tibial vein, although the DVTs that are associated with pulmonary emboli usually arise from DVTs occurring in the veins of the thigh- like the femoral or common femoral veins. DVTs from veins below the knee only have a much better long-term prognosis than those above the knee.
Chronic venous insufficiency is the other main condition associated with the posterior tibial vein. CVI can be asymptomatic, cause cosmetic changes, or in some cases cause severe pain and swelling which can affect quality of life.
References
- Meissner MH. Lower Extremity Venous Anatomy. Seminars in Interventional Radiology [Internet]. 2005 Sep 1;22(3):147–56. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3036282/
- Robert-Ebadi H, Righini M. Management of distal deep vein thrombosis. Thrombosis Research. 2017 Jan;149:48–55.
- Goldhaber SZ, Morrison RB. Pulmonary Embolism and Deep Vein Thrombosis. Circulation. 2002 Sep 17;106(12):1436–8.
- Waheed SM, Hotwagner DT, Kudaravalli P. Deep Vein Thrombosis (DVT) [Internet]. National Library of Medicine. StatPearls Publishing; 2023. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507708/
- Heller T, Becher M, Jens-Christian Kröger, Beller E, Heller S, Raimund Höft, et al. Isolated calf deep venous thrombosis: frequency on venous ultrasound and clinical characteristics. BMC Emergency Medicine. 2021 Oct 30;21(1).
- Youn YJ, Lee J. Chronic venous insufficiency and varicose veins of the lower extremities. The Korean Journal of Internal Medicine. 2019 Mar 1;34(2):269–83.
- Falovic R, Nambiar M, Boekel P, Lenaghan J. Varicose veins causing tibial nerve compression in the tarsal tunnel. BMJ Case Reports. 2019 May;12(5):e230072.